fix: delete agent 500 error + dynamic personality + deployment guide

- Fix delete agent 500: clean up FK records (agent_llm_logs, permissions,
  schedules, executions, team_members) and unbind goals/tasks before delete
- Remove hardcoded personality templates in Android, replace with dynamic
  system prompt generation from name + description
- Set promptSectionsEnabled=false to bypass PromptComposer for personality
- Add Tencent Cloud Linux deployment guide (Docker Compose)
- Accumulated backend service updates, frontend UI fixes, Android app changes

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/models/workflow_version.py

@@ -1,7 +1,7 @@
 """
 工作流版本模型
 """
-from sqlalchemy import Column, String, Text, Integer, DateTime, JSON, ForeignKey, func
+from sqlalchemy import Column, String, Text, Integer, DateTime, JSON, ForeignKey, Index, func
 from sqlalchemy.dialects.mysql import CHAR
 from sqlalchemy.orm import relationship
 from app.core.database import Base
@@ -24,6 +24,11 @@ class WorkflowVersion(Base):
     created_at = Column(DateTime, default=func.now(), comment="创建时间")
     comment = Column(Text, comment="版本备注")
 
+    __table_args__ = (
+        Index("idx_wv_workflow_id", "workflow_id"),
+        Index("idx_wv_status", "status"),
+    )
+
     # 关系
     workflow = relationship("Workflow", backref="versions")
     creator = relationship("User", foreign_keys=[created_by])