Refactor Linux hotkey handling and improve installation process

- Removed the legacy HTTP daemon for handling hotkey presses on Linux, replacing it with a simpler command-based approach using `--action=toggle`.
- Updated the build script to support non-interactive installation for CI environments with the `--no-install` flag.
- Enhanced the ydotool setup process to prefer distribution-provided systemd units and improved error messages for missing dependencies.
- Changed the way active window titles are retrieved on Linux to avoid using robotgo, which can fail on Wayland.
- Updated README and frontend hints to clarify the use of GlobalShortcuts portal and fallback commands for Linux.
- Improved package building scripts to allow building only Debian or RPM packages based on command-line flags.
- Adjusted the text insertion logic to handle different versions of ydotool more robustly.

active_window_linux.go

@@ -0,0 +1,11 @@
+//go:build linux
+
+package main
+
+// activeWindowTitle intentionally avoids robotgo on Linux. robotgo reads X11
+// state directly and can fail or emit noisy errors on Wayland. Refinement is
+// optional, so an empty application-context string is safer than risking a
+// failed transcription after recording has completed.
+func activeWindowTitle() string {
+	return ""
+}