fix(git-tools): harden gitea pr metadata wrappers

packages/mosaic/framework/tools/git/detect-platform.sh

@@ -143,6 +143,37 @@ get_gitea_token() {
     return 1
 }
 
+# Resolve HTTPS basic auth credentials for a Gitea host from ~/.git-credentials.
+# Prints "username:password" for direct curl -u consumption. Callers must not log it.
+get_gitea_basic_auth() {
+    local host="$1"
+    local creds="$HOME/.git-credentials"
+    if [[ ! -f "$creds" ]]; then
+        return 1
+    fi
+
+    python3 - "$host" "$creds" <<'PY'
+import sys
+from pathlib import Path
+from urllib.parse import unquote, urlparse
+
+host = sys.argv[1]
+creds = Path(sys.argv[2])
+
+for line in creds.read_text(encoding="utf-8").splitlines():
+    parsed = urlparse(line.strip())
+    if parsed.hostname != host:
+        continue
+    username = unquote(parsed.username or "")
+    password = unquote(parsed.password or "")
+    if username and password:
+        print(f"{username}:{password}")
+        raise SystemExit(0)
+
+raise SystemExit(1)
+PY
+}
+
 # If script is run directly (not sourced), output the platform
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
     detect_platform