refactor: restructure project layout

- Move main process to electron/main/
- Move preload to electron/preload/
- Add shared types in electron/shared/
- Split redis-service into modular redis/ directory
- Flatten renderer to src/ (remove src/renderer/ nesting)
- Update electron.vite.config.ts paths
- Update tsconfig paths
- Output to electron-dist/

tsconfig.node.json

@@ -6,9 +6,9 @@
     "strict": true,
     "esModuleInterop": true,
     "skipLibCheck": true,
-    "outDir": "./out",
+    "outDir": "./electron-dist",
     "types": ["node"],
     "composite": true
   },
-  "include": ["src/main/**/*", "src/preload/**/*", "electron.vite.config.ts"]
+  "include": ["electron/main/**/*", "electron/preload/**/*", "electron/shared/**/*", "electron.vite.config.ts"]
 }