feat: add privacy mode, thinking levels, PWA support, and i18n

- Add privacy mode to hide IP and user preferences from AI requests
- Add model thinking levels (low/medium/high) for context analysis depth
- Add PWA support with service worker, manifest, and app icons
- Add SettingsPanel for user preferences (theme, background, language)
- Add i18n translations for en/zh/ja/ko/de/fr
- Add Pinia store for centralized settings management
- Update backend to support user preferences and thinking levels
- Update config to use absolute API URLs

src/plugins/copilotPlugin.ts

@@ -51,11 +51,11 @@ export const copilotGhostMark = $markSchema('copilot_ghost', () => ({
   toDOM: () => ['span', { 'data-copilot-ghost': '', class: 'copilot-ghost-text' }, 0],
   parseMarkdown: {
     match: () => false,
-    runner: () => {}
+    runner: () => { }
   },
   toMarkdown: {
     match: (mark) => mark.type.name === 'copilot_ghost',
-    runner: () => {}
+    runner: () => { }
   }
 }))
 
@@ -331,7 +331,7 @@ function scheduleFetch(view: EditorView, runtime: CopilotRuntime, pos: number) {
   const doc = view.state.doc
   const schema = view.state.schema
   const baseSize = doc.content.size
-  
+
   const serializer = runtime.ctx.get(serializerCtx)
   let prefixMarkdown = ''
   let suffixMarkdown = ''
@@ -356,7 +356,7 @@ function scheduleFetch(view: EditorView, runtime: CopilotRuntime, pos: number) {
   const totalTextLen = (prefixMarkdown + suffixMarkdown).length
   const ocrContextLen = requestPrefix.length - prefixMarkdown.length
   const totalWithOcr = totalTextLen + ocrContextLen
-  
+
   const overLimit = totalWithOcr > SIZE_LIMIT
 
   if (overLimit) {