v2.0: Major feature update

New Features:
- API key authentication for external access
- Apple Shortcuts integration endpoint (/api/v1/add)
- Full-text search across all articles
- Folders for organizing articles
- Highlights and notes on articles
- Reading stats with streaks
- Reading goals (daily/weekly/monthly)
- Import from Pocket/Instapaper
- RSS feed output
- PWA support for mobile
- Auto theme scheduling (day/night)
- Settings page with all configuration

API Endpoints:
- /api/v1/add - Add articles via API key
- /api/keys - Manage API keys
- /api/search - Full-text search
- /api/folders - Folder management
- /api/highlights - Highlights/notes
- /api/stats - Reading statistics
- /api/goals - Reading goals
- /api/import - Pocket/Instapaper import
- /api/rss - RSS feed

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/lib/types.ts

@@ -10,12 +10,36 @@ export interface Article {
   leadImage: string | null;
   wordCount: number;
   readingProgress: number;
+  readingTimeSeconds: number;
   isFavorite: boolean;
   isArchived: boolean;
+  folderId: string | null;
   tags: string;
   createdAt: string;
   updatedAt: string;
   readAt: string | null;
+  finishedAt: string | null;
+}
+
+export interface Folder {
+  id: string;
+  name: string;
+  color: string;
+  icon: string;
+  parentId: string | null;
+  sortOrder: number;
+  createdAt: string;
+}
+
+export interface Highlight {
+  id: string;
+  articleId: string;
+  text: string;
+  note: string | null;
+  color: string;
+  startOffset: number | null;
+  endOffset: number | null;
+  createdAt: string;
 }
 
 export interface ReaderSettings {
@@ -24,6 +48,9 @@ export interface ReaderSettings {
   lineHeight: number; // 1.4-2.2
   maxWidth: number; // 500-900
   theme: "dark" | "light" | "sepia";
+  autoTheme: boolean;
+  dayTheme: "dark" | "light" | "sepia";
+  nightTheme: "dark" | "light" | "sepia";
 }
 
 export interface TTSSettings {
@@ -33,12 +60,32 @@ export interface TTSSettings {
   kokoroUrl: string;
 }
 
+export interface ReadingStats {
+  date: string;
+  articlesRead: number;
+  articlesAdded: number;
+  wordsRead: number;
+  timeSpentSeconds: number;
+  streak: number;
+}
+
+export interface ReadingGoal {
+  id: string;
+  type: "daily" | "weekly" | "monthly";
+  metric: "articles" | "words" | "time";
+  target: number;
+  isActive: boolean;
+}
+
 export const defaultReaderSettings: ReaderSettings = {
   fontSize: 18,
   fontFamily: "serif",
   lineHeight: 1.8,
   maxWidth: 700,
   theme: "dark",
+  autoTheme: false,
+  dayTheme: "light",
+  nightTheme: "dark",
 };
 
 export const defaultTTSSettings: TTSSettings = {