702b733074
Every consumer of /wallpapers/*.jpg — SettingsPanel, VideoPlayback, frameRenderer — was doing async IPC round trips, useEffect dances, and Promise.all for a value that is a build-time constant per process. Each consumer showed briefly-empty or briefly-404ing state on first paint until the handler's reply resolved. The asset base URL depends only on process.defaultApp and process.resourcesPath / __dirname — all available in preload at context-bridge time. Compute once there, expose as a sync string. - preload.ts resolves baseDir (process.resourcesPath packaged, <appRoot>/public unpackaged) and emits assetBaseUrl synchronously. - get-asset-base-path IPC handler + main-process branching deleted. - getAssetPath() is now sync. Returns string, not Promise<string>. Throws AssetBaseUnavailableError (new) when electronAPI.assetBaseUrl is missing — catastrophic preload failure, not silent 404. - resolveImageWallpaperUrl() sync; same sync throw semantics. - SettingsPanel: Promise.all + useState + useEffect collapse to one useMemo. First paint has real URLs, no 18× ERR_FILE_NOT_FOUND, no flicker. - VideoPlayback: wallpaper-resolve useEffect collapses to useMemo. - frameRenderer.setupBackground: drops the await. - electronAPI type decls updated in both .d.ts files. - 35 unit tests updated to reflect sync signature + new AssetBaseUnavailableError contract. Silent-fallback behavior from getAssetPath (returning /relative when electronAPI failed) is gone. Renderers now surface preload failures instead of rendering 404s.