refactor(html-scraper): normalize Content-Type and inject httpx client

- Inject httpx.Client for testability and reuse
- Validate and normalize Content-Type header before returning Content
- Emit ContentType.HTML instead of raw header strings
- Avoid per-request client creation
- Preserve metadata while allowing caller overrides

omniread/html/scraper.py

@@ -1,13 +1,13 @@
 import httpx
 from typing import Any, Mapping, Optional
 
-from omniread.core.content import Content
+from omniread.core.content import Content, ContentType
 from omniread.core.scraper import BaseScraper
 
 
 class HTMLScraper(BaseScraper):
     """
-    Base HTTP scraper using httpx.
+    Base HTML scraper using httpx.
 
     Fetches raw bytes and metadata only.
     """
@@ -15,13 +15,16 @@ class HTMLScraper(BaseScraper):
     def __init__(
         self,
         *,
+        client: httpx.Client | None = None,
         timeout: float = 15.0,
         headers: Optional[Mapping[str, str]] = None,
         follow_redirects: bool = True,
     ):
-        self.timeout = timeout
-        self.headers = dict(headers) if headers else {}
-        self.follow_redirects = follow_redirects
+        self._client = client or httpx.Client(
+            timeout=timeout,
+            headers=headers,
+            follow_redirects=follow_redirects,
+        )
 
     def fetch(
         self,
@@ -29,20 +32,16 @@ class HTMLScraper(BaseScraper):
         *,
         metadata: Optional[Mapping[str, Any]] = None,
     ) -> Content:
-        with httpx.Client(
-            timeout=self.timeout,
-            headers=self.headers,
-            follow_redirects=self.follow_redirects,
-        ) as client:
-            response = client.get(source)
-            response.raise_for_status()
+        response = self._client.get(source)
+        response.raise_for_status()
 
         return Content(
             raw=response.content,
             source=source,
-            content_type=response.headers.get("Content-Type"),
+            content_type=ContentType.HTML,
             metadata={
                 "status_code": response.status_code,
                 "headers": dict(response.headers),
+                **(metadata or {}),
             },
         )