feat: add Quick Prompt global hotkey popup for one-off AI questions

Add a system-wide global hotkey (Win+Shift+A / Cmd+Shift+A) that summons
a floating, frameless popup window for quick AI interactions from any app.

Main process:
- GlobalHotkeyService for registering/unregistering system-wide shortcuts
- Frameless, transparent, always-on-top BrowserWindow factory
- IPC handlers for send, discard, close, continue-in-aryx, cancel
- Session event routing from sidecar to quick prompt window
- Settings persistence for default model, hotkey, and reasoning effort

Renderer (separate lightweight entry):
- QuickPromptApp with session state, streaming, keyboard shortcuts
- QuickPromptInput with model selector trigger and cancel support
- QuickPromptResponse with streamed markdown and thinking blocks
- QuickPromptActions (Discard / Close / Continue in Aryx)
- ModelSelector dropdown with tier badges and reasoning effort
- Glass Command Bar aesthetic with animated gradient border

Settings:
- Quick Prompt section in SettingsPanel with enable toggle, hotkey
  display, default model selector, and reasoning effort picker

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

electron.vite.config.ts

@@ -20,6 +20,12 @@ export default defineConfig({
   preload: {
     build: {
       outDir: 'dist-electron/preload',
+      rollupOptions: {
+        input: {
+          index: resolve(__dirname, 'src/preload/index.ts'),
+          quickprompt: resolve(__dirname, 'src/preload/quickprompt.ts'),
+        },
+      },
     },
     plugins: [externalizeDepsPlugin()],
     resolve: {
@@ -32,6 +38,12 @@ export default defineConfig({
     root: 'src/renderer',
     build: {
       outDir: 'dist/renderer',
+      rollupOptions: {
+        input: {
+          index: resolve(__dirname, 'src/renderer/index.html'),
+          quickprompt: resolve(__dirname, 'src/renderer/quickprompt.html'),
+        },
+      },
     },
     plugins: [react(), tailwindcss()],
     resolve: {