refactor: split monolithic main.py into services/ + ui/ modules (improve-maintainability)

- main.py: 4360 → 146 lines (96.6% reduction), entry layer only
- services/: rate_limiter, autostart, persona, connection, profile,
  hotspot, content, engagement, scheduler, queue_ops (10 business modules)
- ui/app.py: all Gradio UI code extracted into build_app(cfg, analytics)
- Fix: with gr.Blocks() indented inside build_app function
- Fix: cfg.all property (not get_all method)
- Fix: STATUS_LABELS, get_persona_keywords, fetch_proactive_notes imports
- Fix: queue_ops module-level set_publish_callback moved into configure()
- Fix: pub_queue.format_*() wrapped as queue_format_table/calendar helpers
- All 14 files syntax-verified, build_app() runtime-verified
- 58/58 tasks complete"

openspec/changes/improve-maintainability/specs/services-persona/spec.md

@@ -0,0 +1,16 @@
+## ADDED Requirements
+
+### Requirement: 人设管理函数及常量迁移至独立模块
+系统 SHALL 将人设相关的常量和函数从 `main.py` 提取至 `services/persona.py`，包括：`DEFAULT_PERSONAS`、`RANDOM_PERSONA_LABEL`、`PERSONA_POOL_MAP`、`DEFAULT_TOPICS`、`DEFAULT_STYLES`、`DEFAULT_COMMENT_KEYWORDS`、`_match_persona_pools`、`get_persona_topics`、`get_persona_keywords`、`on_persona_changed`、`_resolve_persona`。
+
+#### Scenario: 常量可从模块导入
+- **WHEN** `main.py` 执行 `from services.persona import DEFAULT_PERSONAS, PERSONA_POOL_MAP`
+- **THEN** 常量值 SHALL 与迁移前完全一致
+
+#### Scenario: 人设解析正确处理随机人设标签
+- **WHEN** `_resolve_persona(RANDOM_PERSONA_LABEL)` 被调用
+- **THEN** SHALL 返回从人设池中随机选取的人设文本，行为与迁移前一致
+
+#### Scenario: 人设变更回调正常触发
+- **WHEN** `on_persona_changed(persona_text)` 被调用
+- **THEN** SHALL 返回更新后的话题列表和关键词列表，供 Gradio UI 使用