feat(providers): add Cline free-tier models and sync Freebuff catalog

- Cline: 6 free models, cline-cli product headers, API-key auth,
  {data} envelope unwrap, workos: prefix handling
- Freebuff: muse-spark 1.3 → 1.2 (upstream withdrawal 2026-09-07),
  DeepSeek V4.1 Flash rename

open-sse/providers/registry/cline.js

@@ -14,6 +14,9 @@ export default {
     },
   },
   category: "oauth",
+  authModes: ["oauth", "apikey"],
+  hasOAuth: true,
+  authHint: "API key dari app.cline.bot → Settings > API Keys, atau login OAuth via browser.",
   transport: {
     baseUrl: "https://api.cline.bot/api/v1/chat/completions",
     headers: {
@@ -26,6 +29,9 @@ export default {
       combined: true,
       header: "Authorization",
       scheme: "bearer",
+      // Hook owns Authorization: workos:-prefixed OAuth vs plain API key
+      // (a merged token can't express both) — see applyAuth.
+      preserveHookAuth: true,
       hooks: [
         "clineHeaders",
       ],
@@ -40,6 +46,16 @@ export default {
     { id: "google/gemini-3.1-pro-preview", name: "Gemini 3.1 Pro Preview" },
     { id: "google/gemini-3.1-flash-lite-preview", name: "Gemini 3.1 Flash Lite Preview" },
     { id: "kwaipilot/kat-coder-pro", name: "KAT Coder Pro" },
+    // Free tier (verified live via GET /api/v1/ai/cline/recommended-models):
+    // billed $0 on usage, limited quota separate from ClinePass. The
+    // cline-free/* aliases require Cline product headers (see shared/clineAuth.js)
+    // or upstream 403s with "only available via Cline product surfaces".
+    { id: "cline-free/muse-spark-1.3-contributor", name: "Muse Spark 1.3 (Free)" },
+    { id: "deepseek/deepseek-v4-flash", name: "DeepSeek V4 Flash (Free)" },
+    { id: "z-ai/glm-5.3-flash", name: "GLM 5.3 Flash (Free)" },
+    { id: "cline-free/solar-pro4", name: "Solar Pro 4 (Free)" },
+    { id: "cline-free/longcat-2.0", name: "LongCat 2.0 (Free)" },
+    { id: "poolside/laguna-s-2.1:free", name: "Laguna S 2.1 (Free)" },
   ],
   oauth: {
     appBaseUrl: "https://app.cline.bot",