Fix Flatpak source build: binary paths, wasm skip, lockfile patching, metainfo

- Fix protoc paths (strip-components flattens archive structure)
- Patch lockfile at build time for nested workspace deps missing resolved URLs
- Skip wasm-pack build (pre-built wasm is checked into repo)
- Use cargo build directly instead of tauri CLI (avoids inotify limits)
- Fix binary name/path (yaak-app from workspace root target dir)
- Install icons from source tree instead of deb bundle
- Generate desktop file inline instead of extracting from deb
- Add metainfo as file source (not in tagged release yet)
- Add build-wasm.cjs script with SKIP_WASM_BUILD env var support
- Update generate-sources.sh to resolve nested node_modules deps

scripts/build-wasm.cjs

@@ -0,0 +1,8 @@
+const { execSync } = require('node:child_process');
+
+if (process.env.SKIP_WASM_BUILD === '1') {
+  console.log('Skipping wasm-pack build (SKIP_WASM_BUILD=1)');
+  return;
+}
+
+execSync('wasm-pack build --target bundler', { stdio: 'inherit' });