Add HeXi bot codebase: custom plugins, web frontends, tests

- hexi core: message handling, rate limiting, cooldown, plugin manager
- Custom plugins: BF stats, daily check-in, quotes, persona cards, etc.
- Community plugins vendored under hexi/plugins with local fixes
- Web admin frontends (learning-chat, persona-admin), unified hexi/web
- Tests for rate_limit/cooldown/memes/persona; poetry.lock

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

hexi/plugins/nonebot_plugin_video_analysis/__init__.py

@@ -0,0 +1,22 @@
+"""视频解析插件 — 入口（元数据 + 依赖 + 配置注册）。
+
+业务入口在 handlers/entry.py，配置注册在 config.py。
+"""
+
+from nonebot import require
+from nonebot.plugin import PluginMetadata
+
+require("nonebot_plugin_alconna")
+
+__plugin_meta__ = PluginMetadata(
+    name="视频解析",
+    description="解析分享的抖音/哔哩哔哩/YouTube等视频链接",
+    usage="发送视频分享链接自动解析;@bot 时主动触发解析",
+    type="application",
+)
+
+# 显式导入子模块：注册配置 schema + 消息 matcher(配合 load_plugins 只加载到包层)
+from . import config as _config  # noqa: E402
+from . import handlers as _handlers  # noqa: E402
+
+_config.register_config()