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_huoziyinshua/HuoZiYinShua/dictionary.json

@@ -0,0 +1,38 @@
+{
+	"a": "ei",
+	"b": "bi",
+	"c": "xi",
+	"d": "di",
+	"e": "yi",
+	"f": "ai fu",
+	"g": "ji",
+	"h": "ai chi",
+	"i": "ai",
+	"j": "zhei",
+	"k": "kei",
+	"l": "ai lu",
+	"m": "ai mu",
+	"n": "en",
+	"o": "ou",
+	"p": "pi",
+	"q": "kiu",
+	"r": "a",
+	"s": "ai si",
+	"t": "ti",
+	"u": "you",
+	"v": "wei",
+	"w": "da bu liu",
+	"x": "ai ke si",
+	"y": "wai",
+	"z": "zei",
+	"0": "ling",
+	"1": "yi",
+	"2": "er",
+	"3": "san",
+	"4": "si",
+	"5": "wu",
+	"6": "liu",
+	"7": "qi",
+	"8": "ba",
+	"9": "jiu"
+}