feat(prompts+i18n): add prompt management and improve prompt editor i18n (#193)

* feat(prompts): add prompt management across Tauri service and React UI

- backend: add commands/prompt.rs, services/prompt.rs, register in commands/mod.rs and lib.rs, refine app_config.rs
- frontend: add PromptPanel, PromptFormModal, PromptListItem, MarkdownEditor, usePromptActions, integrate in App.tsx
- api: add src/lib/api/prompts.ts
- i18n: update src/i18n/locales/{en,zh}.json
- build: update package.json and pnpm-lock.yaml

* feat(i18n): improve i18n for prompts and Markdown editor

- update src/i18n/locales/{en,zh}.json keys and strings
- apply i18n in PromptFormModal, PromptPanel, and MarkdownEditor
- align prompt text with src-tauri/src/services/prompt.rs

* feat(prompts): add enable/disable toggle and simplify panel UI

- Add PromptToggle component and integrate in prompt list items
- Implement toggleEnabled with optimistic update; enable via API, disable via upsert with enabled=false;
  reload after success
- Simplify PromptPanel: remove file import and current-file preview to keep CRUD flow focused
- Tweak header controls style (use mcp variant) and minor copy: rename “Prompt Management” to “Prompts”
- i18n: add disableSuccess/disableFailed messages
- Backend (Tauri): prevent duplicate backups when importing original prompt content

* style: unify code formatting with trailing commas

* feat(prompts): add Gemini filename support to PromptFormModal

Update filename mapping to use Record<AppId, string> pattern, supporting
GEMINI.md alongside CLAUDE.md and AGENTS.md.

* fix(prompts): sync enabled prompt to file when updating

When updating a prompt that is currently enabled, automatically sync
the updated content to the corresponding live file (CLAUDE.md/AGENTS.md/GEMINI.md).

This ensures the active prompt file always reflects the latest content
when editing enabled prompts.

package.json

@@ -37,6 +37,7 @@
   "dependencies": {
     "@codemirror/lang-javascript": "^6.2.4",
     "@codemirror/lang-json": "^6.0.2",
+    "@codemirror/lang-markdown": "^6.5.0",
     "@codemirror/lint": "^6.8.5",
     "@codemirror/state": "^6.5.2",
     "@codemirror/theme-one-dark": "^6.1.3",