feat: Phase 4 多租户隔离 + 四阶段升级测试 + CSS 统一化

Phase 4: org_id 注入 JWT/API 过滤/组织管理 CRUD/前端组织列
测试: tests/test_phase_upgrades.py 97项全覆盖
CSS: theme-modern.css 共享 mobile-card-list/status-dot/search-bar 等模式
修复: initial_data.py LLM配置 NOT NULL 约束, TopicResponse 含 org_id

platform/backend/app/models.py

@@ -41,6 +41,7 @@ class User(Base):
     username = Column(String, unique=True, nullable=False, index=True)
     password_hash = Column(String, nullable=False)
     role = Column(String, default="user", nullable=False)
+    org_id = Column(String, default="default", nullable=True)
     last_login = Column(DateTime(timezone=True), nullable=True)
     created_at = Column(DateTime(timezone=True), server_default=func.now())
     updated_at = Column(DateTime(timezone=True), onupdate=func.now())
@@ -50,6 +51,7 @@ class User(Base):
             "id": self.id,
             "username": self.username,
             "role": self.role,
+            "org_id": self.org_id,
             "last_login": self.last_login.isoformat() if self.last_login else None,
             "created_at": self.created_at.isoformat() if self.created_at else None
         }
@@ -153,6 +155,7 @@ class Topic(Base):
     id = Column(String, primary_key=True, index=True)
     field_id = Column(Integer, ForeignKey("topic_fields.id"), nullable=True)
     field_name = Column(String, nullable=True)
+    org_id = Column(String, default="default", nullable=True)
     title = Column(String, nullable=False)
     format = Column(String)
     core_concept = Column(Text)
@@ -199,6 +202,7 @@ class Article(Base):
     html_content = Column(Text)
     word_count = Column(Integer, nullable=True)
     outline = Column(Text, nullable=True)
+    images = Column(JSON, default=dict)  # {"cover": "/path/to/cover.png", "chart": "/path/to/chart.png"}
 
 
 class PublishRecord(Base):
@@ -482,6 +486,9 @@ class LLMConfig(Base):
     temperature = Column(Float, default=0.7)
     max_tokens = Column(Integer, default=2000)
     model = Column(String, nullable=True)
+    provider = Column(String, default="opencode-go")  # opencode-go / nvidia
+    base_url = Column(String, nullable=True)
+    api_key = Column(String, nullable=True)
     is_active = Column(Boolean, default=True)
     created_at = Column(DateTime(timezone=True), server_default=func.now())
     updated_at = Column(DateTime(timezone=True), onupdate=func.now())
@@ -495,6 +502,9 @@ class LLMConfig(Base):
             "temperature": self.temperature,
             "max_tokens": self.max_tokens,
             "model": self.model,
+            "provider": self.provider,
+            "base_url": self.base_url,
+            "api_key": f"{self.api_key[:8]}..." if self.api_key else None,
             "is_active": self.is_active,
             "created_at": self.created_at.isoformat() if self.created_at else None,
             "updated_at": self.updated_at.isoformat() if self.updated_at else None,
@@ -520,4 +530,68 @@ class SystemConfig(Base):
             "description": self.description,
             "created_at": self.created_at.isoformat() if self.created_at else None,
             "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+
+class CollectorCategory(Base):
+    """采集类别（可在运营管理中动态编辑）"""
+    __tablename__ = "collector_categories"
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    name = Column(String, unique=True, nullable=False)
+    description = Column(Text, nullable=True)
+    search_query = Column(String, nullable=True)
+    sort_order = Column(Integer, default=0)
+    is_active = Column(Boolean, default=True)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
+
+    sources = relationship("CollectorSource", back_populates="category", cascade="all, delete-orphan")
+
+    def to_dict(self):
+        return {
+            "id": self.id,
+            "name": self.name,
+            "description": self.description,
+            "search_query": self.search_query,
+            "sort_order": self.sort_order,
+            "is_active": self.is_active,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+
+class CollectorSource(Base):
+    """采集信息源（可在运营管理中动态编辑）"""
+    __tablename__ = "collector_sources"
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    category_id = Column(Integer, ForeignKey("collector_categories.id"), nullable=True)
+    name = Column(String, nullable=False)
+    source_type = Column(String, nullable=False)  # rss / web_search / local
+    url = Column(Text, nullable=True)
+    query = Column(String, nullable=True)
+    credibility = Column(String, default="medium")
+    focus = Column(String, nullable=True)
+    is_active = Column(Boolean, default=True)
+    sort_order = Column(Integer, default=0)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
+
+    category = relationship("CollectorCategory", back_populates="sources")
+
+    def to_dict(self):
+        return {
+            "id": self.id,
+            "category_id": self.category_id,
+            "name": self.name,
+            "source_type": self.source_type,
+            "url": self.url,
+            "query": self.query,
+            "credibility": self.credibility,
+            "focus": self.focus,
+            "is_active": self.is_active,
+            "sort_order": self.sort_order,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
         }