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_bf_bot/text_utils.py

@@ -0,0 +1,33 @@
+import re
+
+
+def convert_to_hours(time_str):
+    """
+    将各种时间格式字符串转换为小时数
+    支持格式示例：
+    - "1 day, 1:49:15" (包含天数)
+    - "1:56:55" (小时:分钟:秒)
+    - "0:06:41" (分钟:秒)
+    - "14:11:36" (小时:分钟:秒)
+    """
+    total_hours = 0.0
+
+    # 处理包含天数的部分
+    if "day" in time_str:
+        days_part, time_part = time_str.split(", ")
+        days = float(re.search(r"\d+", days_part).group())
+        total_hours += days * 24
+        time_str = time_part
+
+    # 分割时间部分
+    parts = list(map(float, time_str.split(":")))
+
+    # 根据时间部分长度计算
+    if len(parts) == 3:  # 时:分:秒
+        total_hours += parts[0] + parts[1] / 60 + parts[2] / 3600
+    elif len(parts) == 2:  # 分:秒
+        total_hours += parts[0] / 60 + parts[1] / 3600
+    elif len(parts) == 1:  # 仅秒
+        total_hours += parts[0] / 3600
+
+    return round(total_hours, 2)