fix(provider): preserve custom headers and add custom-provider User-Agent setting (#635)

src/lib/provider-accounts.ts

@@ -81,6 +81,7 @@ export function legacyProviderToAccount(provider: ProviderWithKeyInfo): Provider
     label: provider.name,
     authMode: provider.type === 'ollama' ? 'local' : 'api_key',
     baseUrl: provider.baseUrl,
+    headers: provider.headers,
     model: provider.model,
     fallbackModels: provider.fallbackModels,
     fallbackAccountIds: provider.fallbackProviderIds,

src/lib/providers.ts

@@ -44,6 +44,7 @@ export interface ProviderConfig {
   type: ProviderType;
   baseUrl?: string;
   apiProtocol?: 'openai-completions' | 'openai-responses' | 'anthropic-messages';
+  headers?: Record<string, string>;
   model?: string;
   fallbackModels?: string[];
   fallbackProviderIds?: string[];
@@ -107,6 +108,7 @@ export interface ProviderAccount {
   authMode: ProviderAuthMode;
   baseUrl?: string;
   apiProtocol?: 'openai-completions' | 'openai-responses' | 'anthropic-messages';
+  headers?: Record<string, string>;
   model?: string;
   fallbackModels?: string[];
   fallbackAccountIds?: string[];