feat: Phase 1 MVP 完成

- 实现实体和关系同时提取（LLM）
- 添加 transcripts/mentions/relations 数据持久化
- 新增 API: 关系列表、转录列表、实体提及位置
- 前端实体高亮显示和图谱联动
- 添加 STATUS.md 跟踪开发进度

backend/db_manager.py

@@ -221,9 +221,81 @@ class DatabaseManager:
         conn.close()
         return [EntityMention(**dict(r)) for r in rows]
 
+    # Transcript operations
+    def save_transcript(self, transcript_id: str, project_id: str, filename: str, full_text: str):
+        """保存转录记录"""
+        conn = self.get_conn()
+        now = datetime.now().isoformat()
+        conn.execute(
+            "INSERT INTO transcripts (id, project_id, filename, full_text, created_at) VALUES (?, ?, ?, ?, ?)",
+            (transcript_id, project_id, filename, full_text, now)
+        )
+        conn.commit()
+        conn.close()
+    
+    def get_transcript(self, transcript_id: str) -> Optional[dict]:
+        """获取转录记录"""
+        conn = self.get_conn()
+        row = conn.execute("SELECT * FROM transcripts WHERE id = ?", (transcript_id,)).fetchone()
+        conn.close()
+        if row:
+            return dict(row)
+        return None
+    
+    def list_project_transcripts(self, project_id: str) -> List[dict]:
+        """列出项目的所有转录"""
+        conn = self.get_conn()
+        rows = conn.execute(
+            "SELECT * FROM transcripts WHERE project_id = ? ORDER BY created_at DESC",
+            (project_id,)
+        ).fetchall()
+        conn.close()
+        return [dict(r) for r in rows]
+    
+    # Relation operations
+    def create_relation(self, project_id: str, source_entity_id: str, target_entity_id: str,
+                       relation_type: str = "related", evidence: str = "", transcript_id: str = ""):
+        """创建实体关系"""
+        conn = self.get_conn()
+        relation_id = str(uuid.uuid4())[:8]
+        now = datetime.now().isoformat()
+        conn.execute(
+            """INSERT INTO entity_relations 
+               (id, project_id, source_entity_id, target_entity_id, relation_type, evidence, transcript_id, created_at)
+               VALUES (?, ?, ?, ?, ?, ?, ?, ?)""",
+            (relation_id, project_id, source_entity_id, target_entity_id, relation_type, evidence, transcript_id, now)
+        )
+        conn.commit()
+        conn.close()
+        return relation_id
+    
+    def get_entity_relations(self, entity_id: str) -> List[dict]:
+        """获取实体的所有关系"""
+        conn = self.get_conn()
+        rows = conn.execute(
+            """SELECT * FROM entity_relations 
+               WHERE source_entity_id = ? OR target_entity_id = ?
+               ORDER BY created_at DESC""",
+            (entity_id, entity_id)
+        ).fetchall()
+        conn.close()
+        return [dict(r) for r in rows]
+    
+    def list_project_relations(self, project_id: str) -> List[dict]:
+        """列出项目的所有关系"""
+        conn = self.get_conn()
+        rows = conn.execute(
+            "SELECT * FROM entity_relations WHERE project_id = ? ORDER BY created_at DESC",
+            (project_id,)
+        ).fetchall()
+        conn.close()
+        return [dict(r) for r in rows]
+
+
 # Singleton instance
 _db_manager = None
 
+
 def get_db_manager() -> DatabaseManager:
     global _db_manager
     if _db_manager is None: