feat: feature-gate local inference dependencies (#7976)

Signed-off-by: DaeHee Lee <lee111dae11@proton.me>
Signed-off-by: jh-block <jhugo@block.xyz>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: jh-block <jhugo@block.xyz>

ui/desktop/src/contexts/FeaturesContext.tsx

@@ -0,0 +1,49 @@
+import { createContext, useContext, useEffect, useState, useMemo } from 'react';
+import { getFeatures } from '../api';
+
+interface FeaturesContextValue {
+  localInference: boolean;
+  codeMode: boolean;
+  isLoading: boolean;
+}
+
+const FeaturesContext = createContext<FeaturesContextValue | null>(null);
+
+export function FeaturesProvider({ children }: { children: React.ReactNode }) {
+  const [features, setFeatures] = useState<Record<string, boolean>>({});
+  const [isLoading, setIsLoading] = useState(true);
+
+  useEffect(() => {
+    (async () => {
+      try {
+        const response = await getFeatures({ throwOnError: false });
+        if (response.data) {
+          setFeatures(response.data.features);
+        }
+      } catch (error) {
+        console.warn('[FeaturesContext] Failed to fetch features:', error);
+      } finally {
+        setIsLoading(false);
+      }
+    })();
+  }, []);
+
+  const value = useMemo<FeaturesContextValue>(
+    () => ({
+      localInference: features['local-inference'] ?? false,
+      codeMode: features['code-mode'] ?? true,
+      isLoading,
+    }),
+    [features, isLoading]
+  );
+
+  return <FeaturesContext.Provider value={value}>{children}</FeaturesContext.Provider>;
+}
+
+export function useFeatures(): FeaturesContextValue {
+  const context = useContext(FeaturesContext);
+  if (!context) {
+    throw new Error('useFeatures must be used within a FeaturesProvider');
+  }
+  return context;
+}