feat: add compact mode for minimal widget interface (#36)

Add a compact mode that shrinks the window to a small widget showing
just the character sprite, recent messages, and a quick input box.
Perfect for quick questions while working without the full UI.

- Add CompactMode.svelte component with minimal widget interface
- Add compact mode toggle in StatusBar (Ctrl+Shift+M shortcut)
- Save/restore window size when toggling compact mode
- Handle display scaling by converting physical to logical pixels
- Add compact_mode to config (Rust + TypeScript)
- Add required Tauri window permissions for resize operations

src/lib/stores/config.ts

@@ -21,6 +21,7 @@ export interface HikariConfig {
   font_size: number;
   streamer_mode: boolean;
   streamer_hide_paths: boolean;
+  compact_mode: boolean;
 }
 
 const defaultConfig: HikariConfig = {
@@ -41,6 +42,7 @@ const defaultConfig: HikariConfig = {
   font_size: 14,
   streamer_mode: false,
   streamer_hide_paths: false,
+  compact_mode: false,
 };
 
 function createConfigStore() {
@@ -155,6 +157,16 @@ function createConfigStore() {
       config.subscribe((c) => (currentConfig = c))();
       await updateConfig({ streamer_mode: !currentConfig.streamer_mode });
     },
+
+    toggleCompactMode: async () => {
+      let currentConfig: HikariConfig = defaultConfig;
+      config.subscribe((c) => (currentConfig = c))();
+      await updateConfig({ compact_mode: !currentConfig.compact_mode });
+    },
+
+    setCompactMode: async (enabled: boolean) => {
+      await updateConfig({ compact_mode: enabled });
+    },
   };
 }
 
@@ -186,6 +198,7 @@ export const configStore = createConfigStore();
 export const isDarkTheme = derived(configStore.config, ($config) => $config.theme === "dark");
 
 export const isStreamerMode = derived(configStore.config, ($config) => $config.streamer_mode);
+export const isCompactMode = derived(configStore.config, ($config) => $config.compact_mode);
 export const shouldHidePaths = derived(
   configStore.config,
   ($config) => $config.streamer_mode && $config.streamer_hide_paths