refactor(open-sse): translator DRY + schema enums, bug fixes, dead code cleanup

- Bug B1-B7: media UI m.kind||m.type, serviceKinds, gemini mediaPriority, schema kind, models/info lookup by kind
- Dead code D1-D6: safeParseJSON, drop PROVIDER_ENDPOINTS, orphan fetcher, GITHUB_CONFIG derive, getProviderConfig internal, legacy kiro file
- Translator concerns: toOpenAIUsage, toOpenAIFinish (gemini/kiro/ollama + fix kiro tool finish), thinking effort maps
- Reorg helpers/ → concerns/ (logic) + formats/ (per-format) + schema/ (pure enums: roles/blocks/finishReasons/defaults)
- Wire ~280 hardcoded role/block/finish/default literals to schema enums across 20+ files
- collapseTextParts + extractTextContent dedup
- Normalize translator fn names to openaiToXRequest / xToOpenAIResponse
- Golden tests lock behavior; 0 regression (byte-for-byte providers/alias, 26=26 known fails)

Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/providers/registry/huggingface.js

@@ -1,5 +1,7 @@
 export default {
   id: "huggingface",
+  priority: 70,
+  hasFree: true,
   alias: "huggingface",
   aliases: [
     "hf",
@@ -27,5 +29,6 @@ export default {
     { id: "openai/whisper-large-v3", name: "Whisper Large v3 (HF)", params: ["language"], kind: "stt" },
     { id: "openai/whisper-small", name: "Whisper Small (HF)", params: ["language"], kind: "stt" },
   ],
+  serviceKinds: ["image", "stt"],
   imageConfig: { baseUrl: "https://api-inference.huggingface.co/models" },
 };