refactor: reorganize Vite config into modular files

Split monolithic vite.config.mjs into separate config files:
- vite.config.web.mts
- vite.config.electron.mts
- vite.config.capacitor.mts
- vite.config.pywebview.mts
- vite.config.common.mts
- vite.config.utils.mts

Updates:
- Modify package.json scripts to use specific config files
- Add electron-builder as dev dependency
- Update electron build configuration
- Fix electron resource paths
- Remove old vite.config.mjs and utils.js

This change improves maintainability by:
- Separating concerns for different build targets
- Making build configurations more explicit
- Reducing complexity in individual config files

vite.config.capacitor.mts

@@ -0,0 +1,4 @@
+import { defineConfig } from "vite";
+import { createBuildConfig } from "./vite.config.common.mts";
+
+export default defineConfig(async () => createBuildConfig('capacitor'));