Phase 5 구현: SQLite DB + History/Dictionary 서비스 + UI

- DB: better-sqlite3 + drizzle-orm (history/dictionary/stats, WAL 모드)
- HistoryService: CRUD + 검색 + 통계 + 30일 보존 정책, 세션 완료 시 자동 저장
- DictionaryService: CRUD + 검색 + 사용 횟수 추적 + STT 프롬프트 힌트
- HistoryPage: 목록 + 검색 + 삭제 + 복사 + 페이지네이션
- DictionaryPage: 목록 + 검색 + 추가 다이얼로그 + 삭제
- DashboardPage: 실데이터 통계 (총/오늘 세션, 시간, 단어수, 연속일수)
- IPC: history/dictionary/stats 핸들러 + preload API
- Bootstrap: DB 초기화 (critical) + 이력 자동 저장 연동

src/main/db/index.ts

@@ -0,0 +1,107 @@
+// src/main/db/index.ts
+// 설계서 03의 DB 초기화 코드
+
+import Database from 'better-sqlite3'
+import { drizzle, type BetterSQLite3Database } from 'drizzle-orm/better-sqlite3'
+import { app } from 'electron'
+import path from 'path'
+import * as schema from './schema'
+import { getLogger } from '../services/LoggerService'
+
+const logger = getLogger('database')
+
+let db: BetterSQLite3Database<typeof schema> | null = null
+let sqlite: Database.Database | null = null
+
+export function initDatabase(): BetterSQLite3Database<typeof schema> {
+  const dbPath = path.join(app.getPath('userData'), 'd3ro-voice.db')
+  logger.info(`Initializing database at: ${dbPath}`)
+
+  sqlite = new Database(dbPath)
+
+  sqlite.pragma('journal_mode = WAL')
+  sqlite.pragma('foreign_keys = ON')
+  sqlite.pragma('busy_timeout = 5000')
+
+  // 테이블 생성 (마이그레이션 대신 직접 생성)
+  sqlite.exec(`
+    CREATE TABLE IF NOT EXISTS history (
+      id                      TEXT PRIMARY KEY,
+      original_text           TEXT NOT NULL,
+      polished_text           TEXT,
+      focused_app             TEXT,
+      focused_app_name        TEXT,
+      focused_app_window_title TEXT,
+      mode                    TEXT NOT NULL DEFAULT 'dictation',
+      status                  TEXT NOT NULL DEFAULT 'completed',
+      error_code              TEXT,
+      audio_local_path        TEXT,
+      duration                REAL NOT NULL,
+      detected_language       TEXT,
+      mic_device              TEXT,
+      word_count              INTEGER NOT NULL DEFAULT 0,
+      stt_model               TEXT,
+      llm_model               TEXT,
+      stt_latency_ms          INTEGER,
+      llm_latency_ms          INTEGER,
+      created_at              INTEGER NOT NULL,
+      updated_at              INTEGER NOT NULL,
+      app_version             TEXT NOT NULL DEFAULT '1.0.0'
+    );
+
+    CREATE INDEX IF NOT EXISTS idx_history_created_at ON history(created_at DESC);
+    CREATE INDEX IF NOT EXISTS idx_history_status ON history(status);
+    CREATE INDEX IF NOT EXISTS idx_history_detected_language ON history(detected_language);
+    CREATE INDEX IF NOT EXISTS idx_history_focused_app_name ON history(focused_app_name);
+    CREATE INDEX IF NOT EXISTS idx_history_mode ON history(mode);
+
+    CREATE TABLE IF NOT EXISTS dictionary (
+      id            TEXT PRIMARY KEY,
+      word          TEXT NOT NULL,
+      pronunciation TEXT,
+      category      TEXT NOT NULL DEFAULT 'user',
+      usage_count   INTEGER NOT NULL DEFAULT 0,
+      last_used_at  INTEGER,
+      created_at    INTEGER NOT NULL,
+      updated_at    INTEGER NOT NULL
+    );
+
+    CREATE UNIQUE INDEX IF NOT EXISTS idx_dictionary_word_category ON dictionary(word, category);
+    CREATE INDEX IF NOT EXISTS idx_dictionary_created_at ON dictionary(created_at);
+    CREATE INDEX IF NOT EXISTS idx_dictionary_usage_count ON dictionary(usage_count DESC);
+
+    CREATE TABLE IF NOT EXISTS stats (
+      id              INTEGER PRIMARY KEY CHECK (id = 1),
+      total_duration  REAL NOT NULL DEFAULT 0,
+      total_words     INTEGER NOT NULL DEFAULT 0,
+      session_count   INTEGER NOT NULL DEFAULT 0,
+      streak_days     INTEGER NOT NULL DEFAULT 0,
+      last_session_at INTEGER,
+      last_updated    INTEGER NOT NULL
+    );
+
+    INSERT OR IGNORE INTO stats (id, total_duration, total_words, session_count, streak_days, last_updated)
+    VALUES (1, 0, 0, 0, 0, ${Date.now()});
+  `)
+
+  db = drizzle(sqlite, { schema })
+
+  logger.info('Database initialized')
+  return db
+}
+
+export function getDatabase(): BetterSQLite3Database<typeof schema> {
+  if (!db) {
+    throw new Error('Database not initialized. Call initDatabase() first.')
+  }
+  return db
+}
+
+export function closeDatabase(): void {
+  if (sqlite) {
+    sqlite.close()
+    sqlite = null
+    db = null
+    logger.info('Database closed')
+  }
+}