Implement Driftwood AppImage manager - Phases 1 and 2

Phase 1 - Application scaffolding:
- GTK4/libadwaita application window with AdwNavigationView
- GSettings-backed window state persistence
- GResource-compiled CSS and schema
- Library view with grid/list toggle, search, sorting, filtering
- Detail view with file info, desktop integration controls
- Preferences window with scan directories, theme, behavior settings
- CLI with list, scan, integrate, remove, clean, inspect commands
- AppImage discovery, metadata extraction, desktop integration
- Orphaned desktop entry detection and cleanup
- AppImage packaging script

Phase 2 - Intelligence layer:
- Database schema v2 with migration for status tracking columns
- FUSE detection engine (libfuse2/3, fusermount, /dev/fuse, AppImageLauncher)
- Wayland awareness engine (session type, toolkit detection, XWayland)
- Update info parsing from AppImage ELF sections (.upd_info)
- GitHub/GitLab Releases API integration for update checking
- Update download with progress tracking and atomic apply
- Launch wrapper with FUSE auto-detection and usage tracking
- Duplicate and multi-version detection with recommendations
- Dashboard with system health, library stats, disk usage
- Update check dialog (single and batch)
- Duplicate resolution dialog
- Status badges on library cards and detail view
- Extended CLI: status, check-updates, duplicates, launch commands

49 tests passing across all modules.

build.rs

@@ -0,0 +1,36 @@
+use std::path::PathBuf;
+use std::process::Command;
+
+fn main() {
+    // Compile GResources
+    glib_build_tools::compile_resources(
+        &["data"],
+        "data/resources.gresource.xml",
+        "driftwood.gresource",
+    );
+
+    // Compile GSettings schema for development builds
+    let out_dir = PathBuf::from(std::env::var("OUT_DIR").unwrap());
+    let schema_dir = out_dir.join("gschemas");
+    std::fs::create_dir_all(&schema_dir).expect("Failed to create schema dir");
+
+    std::fs::copy(
+        "data/app.driftwood.Driftwood.gschema.xml",
+        schema_dir.join("app.driftwood.Driftwood.gschema.xml"),
+    )
+    .expect("Failed to copy schema");
+
+    let status = Command::new("glib-compile-schemas")
+        .arg(&schema_dir)
+        .status()
+        .expect("Failed to run glib-compile-schemas");
+
+    if !status.success() {
+        panic!("glib-compile-schemas failed");
+    }
+
+    println!(
+        "cargo::rustc-env=GSETTINGS_SCHEMA_DIR={}",
+        schema_dir.display()
+    );
+}