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/services/feedback_learner.py

@@ -46,6 +46,8 @@ class FeedbackLearner:
                 severity = 0.6
             elif signal_type == "retry_command":
                 severity = 0.4
+            elif signal_type == "thumbs_up":
+                severity = 0.1
 
             entry = FeedbackRecord(
                 user_id=user_id,
@@ -68,7 +70,7 @@ class FeedbackLearner:
                     AgentExecutionLog.id == execution_log_id
                 ).first()
                 if exec_log:
-                    exec_log.user_rating = 1 if signal_type in ("thumbs_down", "reject_approval") else 3
+                    exec_log.user_rating = 1 if signal_type in ("thumbs_down", "reject_approval") else (5 if signal_type == "thumbs_up" else 3)
                     exec_log.user_feedback = signal_type
 
             db.commit()