fix: Add cross-platform handling for tray, updater, and icon generation

- Add platform notes for tray startup, shortcut saving, and Linux-only settings
- Handle stat error in processRecording (missing file)
- Select correct binary name based on OS in updater
- Increase tray icon canvas size from 64 to 128 pixels
- Update frontend dist asset hash

internal/hotkey/hotkey.go

@@ -83,6 +83,8 @@ func (l *Listener) Start() {
 	}
 
 	if modOnly {
+		// WINDOWS-ONLY FEATURE: Modifier-only shortcuts (e.g. ctrl+win without a key)
+		// are only supported on Windows via modifier polling. On Linux, this is rejected.
 		if runtime.GOOS != "windows" {
 			logger.Error("Modifier-only shortcuts like %q are only supported on Windows", l.shortcut)
 			l.mu.Unlock()

internal/linux/media.go

@@ -1,4 +1,11 @@
 //go:build linux
+
+// ============================================================
+// LINUX-ONLY FILE — Linux media playback management.
+// Uses playerctl to pause/resume media during recording.
+// The Windows equivalent is in internal/windows/
+// ============================================================
+
 package linux
 
 import (

internal/linux/overlay.go

@@ -1,5 +1,12 @@
 //go:build linux
 
+// ============================================================
+// LINUX-ONLY FILE — No-op overlay implementation for Linux.
+// On Linux, the overlay is intentionally disabled (no desktop
+// notifications). The Windows equivalent with full Win32 overlay
+// is in internal/windows/overlay.go
+// ============================================================
+
 package linux
 
 // linuxOverlay intentionally does not show system notifications. Tray status

internal/linux/process.go

@@ -1,4 +1,11 @@
 //go:build linux
+
+// ============================================================
+// LINUX-ONLY FILE — Linux process management utilities.
+// Uses syscall.Kill(pid, 0) to check if a process is running.
+// The Windows equivalent is in internal/windows/process.go
+// ============================================================
+
 package linux
 
 import "syscall"

internal/linux/startup.go

@@ -1,4 +1,12 @@
 //go:build linux
+
+// ============================================================
+// LINUX-ONLY FILE — Linux startup (autostart) management via
+// XDG Desktop Entry files (.desktop). Creates/removes autostart
+// entries and manages the application's .desktop file.
+// The Windows equivalent is in internal/windows/
+// ============================================================
+
 package linux
 
 import (

internal/platform/platform.go

@@ -1,3 +1,11 @@
+// ============================================================
+// CROSS-PLATFORM FILE — This defines the Overlay interface
+// that is implemented differently on each platform:
+//   - Windows:   internal/windows/overlay.go (Win32 overlay)
+//   - Linux:     internal/linux/overlay.go (no-op)
+// This file itself is compiled on ALL platforms.
+// ============================================================
+
 package platform
 
 // Overlay defines the cross-platform interface for screen overlays

internal/platform/platform_linux.go

@@ -1,4 +1,11 @@
 //go:build linux
+
+// ============================================================
+// LINUX-ONLY FILE — Delegates all platform operations to the
+// internal/linux package (overlay, media, startup, process).
+// The Windows equivalent is platform_windows.go
+// ============================================================
+
 package platform
 
 import "wis-free-v3/internal/linux"

internal/platform/platform_windows.go

@@ -1,4 +1,11 @@
 //go:build windows
+
+// ============================================================
+// WINDOWS-ONLY FILE — Delegates all platform operations to the
+// internal/windows package (overlay, media, startup, process).
+// The Linux equivalent is platform_linux.go
+// ============================================================
+
 package platform
 
 import "wis-free-v3/internal/windows"

internal/services/whisper/whisper.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"time"
 
@@ -115,7 +116,13 @@ func (m *Manager) Install(model string) error {
 		return fmt.Errorf("failed to create install directory: %w", err)
 	}
 
-	// Create install script
+	if runtime.GOOS == "linux" || runtime.GOOS == "darwin" {
+		// On Linux/macOS, the automatic installer is not available.
+		// Users should install whisper.cpp from their package manager or build from source.
+		return fmt.Errorf("automatic whisper installation is not available on %s; install whisper.cpp from your package manager (e.g. 'sudo apt install whisper-cpp' or 'brew install whisper-cpp') or build from source at https://github.com/ggerganov/whisper.cpp, then place the binary and model in %s", runtime.GOOS, m.installDir)
+	}
+
+	// Create install script (Windows batch file)
 	scriptPath := filepath.Join(m.installDir, "install.bat")
 	script := m.generateInstallScript(model)
 	if err := os.WriteFile(scriptPath, []byte(script), 0755); err != nil {
@@ -363,11 +370,18 @@ func (m *Manager) getBinaryPath() string {
 	// whisper.cpp extracts to a Release subdirectory
 	releaseDir := filepath.Join(m.installDir, "Release")
 
-	// Try different possible binary names
-	// whisper-cli.exe is the new standard (main.exe is deprecated)
+	// Try different possible binary names (platform-aware)
+	// On Windows: whisper-cli.exe / main.exe
+	// On Linux/macOS: whisper-cli / main
 	possibleNames := []string{
-		"whisper-cli.exe",
-		"main.exe",
+		"whisper-cli",
+		"main",
+	}
+	if runtime.GOOS == "windows" {
+		possibleNames = []string{
+			"whisper-cli.exe",
+			"main.exe",
+		}
 	}
 
 	// First check in Release subdirectory
@@ -386,8 +400,11 @@ func (m *Manager) getBinaryPath() string {
 		}
 	}
 
-	// Default to Release/main.exe
-	return filepath.Join(releaseDir, "main.exe")
+	// Default path
+	if runtime.GOOS == "windows" {
+		return filepath.Join(releaseDir, "main.exe")
+	}
+	return filepath.Join(releaseDir, "main")
 }
 
 // CheckOnline checks if internet is available

internal/ui/tray/tray.go

@@ -279,52 +279,55 @@ func initDynamicIcons() {
 }
 
 func createMicPNG(c color.Color) []byte {
-	img := image.NewRGBA(image.Rect(0, 0, 64, 64))
+	const S = 128 // canvas size
+	img := image.NewRGBA(image.Rect(0, 0, S, S))
 	// All pixels are transparent by default (new RGBA starts with 0 alpha).
 
+	cx, cy := S/2, S/2 // center (64, 50)
+
 	// Let's draw the microphone parts
-	for y := 0; y < 64; y++ {
-		for x := 0; x < 64; x++ {
+	for y := 0; y < S; y++ {
+		for x := 0; x < S; x++ {
 			drawPixel := false
 
 			// 1. Capsule Body (Rounded Rectangle)
-			// Capsule center is X=32, Y=25. Width=14 (radius 7), height of straight part = 10 (Y from 20 to 30)
-			if x >= 25 && x <= 39 && y >= 20 && y <= 30 {
+			// Capsule center is X=64, Y=50. Width=28 (radius 14), height of straight part = 20 (Y from 40 to 60)
+			if x >= 50 && x <= 78 && y >= 40 && y <= 60 {
 				drawPixel = true
-			} else if y < 20 {
-				// Top cap: center (32, 20), radius 7
-				dx := float64(x - 32)
-				dy := float64(y - 20)
-				if dx*dx+dy*dy <= 49 { // 7^2
+			} else if y < 40 {
+				// Top cap: center (64, 40), radius 14
+				dx := float64(x - cx)
+				dy := float64(y - 40)
+				if dx*dx+dy*dy <= 196 { // 14^2
 					drawPixel = true
 				}
-			} else if y > 30 && y <= 37 {
-				// Bottom cap: center (32, 30), radius 7
-				dx := float64(x - 32)
-				dy := float64(y - 30)
-				if dx*dx+dy*dy <= 49 {
+			} else if y > 60 && y <= 74 {
+				// Bottom cap: center (64, 60), radius 14
+				dx := float64(x - cx)
+				dy := float64(y - 60)
+				if dx*dx+dy*dy <= 196 {
 					drawPixel = true
 				}
 			}
 
 			// 2. U-stand
-			// Center of U-stand circle is (32, 25).
-			// Outer radius = 15, inner radius = 12 (thickness 3)
-			// Only draw for Y >= 25 and Y <= 40
-			dx := float64(x - 32)
-			dy := float64(y - 25)
+			// Center of U-stand circle is (64, 50).
+			// Outer radius = 30, inner radius = 24 (thickness 6)
+			// Only draw for Y >= 50 and Y <= 80
+			dx := float64(x - cx)
+			dy := float64(y - cy)
 			distSq := dx*dx + dy*dy
-			if y >= 25 && y <= 40 && distSq >= 144 && distSq <= 225 { // 12^2 to 15^2
+			if y >= 50 && y <= 80 && distSq >= 576 && distSq <= 900 { // 24^2 to 30^2
 				drawPixel = true
 			}
 
-			// 3. Stem (Vertical line from Y=40 to 50, X=31 to 33)
-			if x >= 31 && x <= 33 && y >= 40 && y <= 50 {
+			// 3. Stem (Vertical line from Y=80 to 100, X=62 to 66)
+			if x >= 62 && x <= 66 && y >= 80 && y <= 100 {
 				drawPixel = true
 			}
 
-			// 4. Base (Horizontal line at Y=50 to 52, X=20 to 44)
-			if x >= 20 && x <= 44 && y >= 50 && y <= 52 {
+			// 4. Base (Horizontal line at Y=100 to 104, X=40 to 88)
+			if x >= 40 && x <= 88 && y >= 100 && y <= 104 {
 				drawPixel = true
 			}
 

internal/ui/tray/tray_linux.go

@@ -1,4 +1,10 @@
 //go:build linux
+
+// ============================================================
+// LINUX-ONLY FILE — Sets the GTK program name for the system tray
+// on Linux. This is required for proper desktop integration.
+// ============================================================
+
 package tray
 
 /*

internal/ui/tray/tray_start_linux.go

@@ -1,5 +1,12 @@
 //go:build linux
 
+// ============================================================
+// LINUX-ONLY FILE — Tray startup for Linux. On Linux, Wails'
+// GTK main loop is already running, so we use systray.Register
+// instead of systray.Run (which would start a second gtk_main).
+// The Windows equivalent is tray_start_nonlinux.go
+// ============================================================
+
 package tray
 
 import "github.com/getlantern/systray"

internal/ui/tray/tray_start_nonlinux.go

@@ -1,5 +1,12 @@
 //go:build !linux
 
+// ============================================================
+// WINDOWS-ONLY FILE — Tray startup for Windows (and macOS).
+// Uses systray.Run which blocks and runs the Win32 message pump.
+// The Linux equivalent is tray_start_linux.go which uses
+// systray.Register to integrate with the existing GTK loop.
+// ============================================================
+
 package tray
 
 import (

internal/windows/media.go

@@ -1,4 +1,12 @@
 //go:build windows
+
+// ============================================================
+// WINDOWS-ONLY FILE — Windows media playback management.
+// Uses Win32 keybd_event to send VK_MEDIA_PLAY_PAUSE and a
+// PowerShell script to check media playback state via SMTC.
+// The Linux equivalent is internal/linux/media.go (playerctl)
+// ============================================================
+
 package windows
 
 import (

internal/windows/overlay.go

@@ -1,4 +1,12 @@
 //go:build windows
+
+// ============================================================
+// WINDOWS-ONLY FILE — Native Windows overlay window using
+// Win32 API directly (CreateWindowEx, GDI drawing, etc.).
+// This shows a pill-shaped overlay on screen during recording.
+// The Linux equivalent is internal/linux/overlay.go (no-op).
+// ============================================================
+
 package windows
 
 import (

internal/windows/process.go

@@ -1,4 +1,12 @@
 //go:build windows
+
+// ============================================================
+// WINDOWS-ONLY FILE — Windows process management utilities.
+// Uses Win32 API (OpenProcess, GetExitCodeProcess) to check
+// if a process is running. The Linux equivalent for process
+// checking is in internal/linux/process.go
+// ============================================================
+
 package windows
 
 import (

internal/windows/startup.go

@@ -1,4 +1,12 @@
 //go:build windows
+
+// ============================================================
+// WINDOWS-ONLY FILE — Windows startup (autostart) management
+// via the Windows Registry (HKCU\Software\Microsoft\Windows\
+// CurrentVersion\Run). The Linux equivalent for autostart
+// management is internal/linux/startup.go (XDG .desktop files)
+// ============================================================
+
 package windows
 
 import (

internal/xhotkey/hotkey_linux_portal.go

@@ -1,5 +1,12 @@
 //go:build linux
 
+// ============================================================
+// LINUX-ONLY FILE — Portal-based global hotkey implementation
+// for Linux using the org.freedesktop.portal.GlobalShortcuts
+// D-Bus API (Wayland/desktop-agnostic).
+// The Windows equivalent is in hotkey_windows.go
+// ============================================================
+
 package hotkey
 
 import (