harden: bound HTTP reads and enforce strict redirects (#3140)

* harden: bound HTTP reads and enforce strict redirects

Add a shared _download_security module (read_response_limited,
is_https_or_localhost_http, size constants) and route the GitHub release
and Azure DevOps token network reads through bounded reads so an oversized
response can't exhaust memory.

Add a strict_redirects mode to authentication.open_url: the redirect handler
now rejects any redirect whose target isn't HTTPS (or HTTP to localhost),
composing with the existing per-hop redirect_validator and auth-stripping.
The Azure DevOps token POST is routed through that handler so a 307/308
cannot forward the client_secret body to a non-HTTPS host.

Assisted-by: Codex (model: GPT-5, autonomous)

* test: align HTTP fakes with bounded reads

Assisted-by: Codex (model: GPT-5, autonomous)

* fix: tolerate invalid token response encoding

Assisted-by: Codex (model: GPT-5, autonomous)

* test: align GHES fakes with bounded reads

Assisted-by: Codex (model: GPT-5, autonomous)

* test: reuse shared upgrade HTTP response helper

Assisted-by: Codex (model: GPT-5, autonomous)

* fix: include rejected redirect target in error

Assisted-by: Codex (model: GPT-5, autonomous)

* fix: enforce strict redirects by default

Assisted-by: Codex (model: GPT-5, autonomous)

* fix: close redirect credential and SSRF gaps

Assisted-by: Codex (model: GPT-5, autonomous)

src/specify_cli/_github_http.py

@@ -100,6 +100,8 @@ def resolve_github_release_asset_api_url(
     import json
     import urllib.error
 
+    from specify_cli._download_security import read_response_limited
+
     parsed = urlparse(download_url)
     hostname = (parsed.hostname or "").lower()
     parts = [unquote(part) for part in parsed.path.strip("/").split("/")]
@@ -158,10 +160,13 @@ def resolve_github_release_asset_api_url(
         if redirect_validator is not None:
             open_kwargs["redirect_validator"] = redirect_validator
         with open_url_fn(release_url, **open_kwargs) as response:
-            raw_release_data = response.read(max_metadata_bytes + 1)
-            if len(raw_release_data) > max_metadata_bytes:
-                raise ValueError("GitHub release metadata exceeds size limit")
-            release_data = json.loads(raw_release_data)
+            release_data = json.loads(
+                read_response_limited(
+                    response,
+                    max_bytes=max_metadata_bytes,
+                    label=f"GitHub release metadata {release_url}",
+                )
+            )
     except (
         urllib.error.URLError,
         json.JSONDecodeError,