fix: enrich default models with SDK metadata instead of replacing

The SDK's supportedModels() returns a different set than our defaults —
missing opus, including a "default" alias that duplicates sonnet. Instead
of replacing our curated model list, enrich it with SDK capability
metadata (supportsEffort, etc.) while keeping our list and display names
as the source of truth.

Fixes: Opus 4.6 disappearing and duplicate Sonnet 4.6 entries.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: jasonjaclyn2017

src/app/api/providers/models/route.ts

@@ -65,21 +65,24 @@ export async function GET() {
       }),
     });
 
-    // If SDK has discovered models, use them for the env group
+    // Enrich default models with SDK capability metadata (supportsEffort, etc.)
+    // but keep our curated list and display names as the source of truth.
+    // The SDK may return different aliases ("default"), missing models, or
+    // different display names — we don't let that override our defaults.
     try {
       const { getCachedModels } = await import('@/lib/agent-sdk-capabilities');
       const sdkModels = getCachedModels('env');
       if (sdkModels.length > 0) {
-        groups[0].models = sdkModels.map(m => {
-          const cw = getContextWindow(m.value);
+        const sdkByValue = new Map(sdkModels.map(m => [m.value, m]));
+        groups[0].models = groups[0].models.map(m => {
+          const sdk = sdkByValue.get(m.value);
+          if (!sdk) return m;
           return {
-            value: m.value,
-            label: CLAUDE_MODELS[m.value as keyof typeof CLAUDE_MODELS]?.displayName ?? m.displayName,
-            description: m.description,
-            supportsEffort: m.supportsEffort,
-            supportedEffortLevels: m.supportedEffortLevels,
-            supportsAdaptiveThinking: m.supportsAdaptiveThinking,
-            ...(cw != null ? { contextWindow: cw } : {}),
+            ...m,
+            description: sdk.description,
+            supportsEffort: sdk.supportsEffort,
+            supportedEffortLevels: sdk.supportedEffortLevels,
+            supportsAdaptiveThinking: sdk.supportsAdaptiveThinking,
           };
         });
       }