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>

frontend/Dockerfile

@@ -9,6 +9,7 @@ RUN pnpm build
 # 运行阶段
 FROM nginx:alpine
 COPY --from=builder /app/dist /usr/share/nginx/html
+COPY nginx-main.conf /etc/nginx/nginx.conf
 COPY nginx.conf /etc/nginx/conf.d/default.conf
 EXPOSE 80
 CMD ["nginx", "-g", "daemon off;"]