refactor: convert HttpResponse to frozen dataclass

text becomes a derived property; reason is now optional.

src/byteb4rb1e/utils/http/client.py

@@ -5,6 +5,7 @@ Thin urllib wrapper with retry-on-rate-limit.  No domain knowledge —
 GitHub, Bitbucket, etc. are handled by higher-level modules.
 """
 
+from dataclasses import dataclass
 import json
 import time
 from typing import Any, Dict, Optional
@@ -13,17 +14,20 @@ import urllib.parse
 from warnings import warn
 
 
+@dataclass(frozen=True)
 class HttpResponse:
-    def __init__(self, status: int, headers: dict, data: bytes, reason: str):
+    status_code: int
-        self.status_code = status
+    headers: dict[str, str]
-        self.headers = headers
+    data: bytes
-        self.data = data
+    reason: Optional[str] = None
-        self.reason = reason
-        self.text = data.decode("utf-8", errors="replace")
 
     def json(self):
         return json.loads(self.data.decode("utf-8"))
 
+    @property
+    def text(self) -> str:
+        return self.data.decode("utf-8", errors="replace")
+
 
 def _request(
     url: str,