fix(litellm): final parity gaps from second audit

- blocks/utils.ts getModelOptions(): include litellm models in the
  combined model dropdown — was previously dropping any
  proxy-discovered models from the agent block model picker.
- get-blocks-metadata-tool.ts mockProvidersState: add litellm bucket
  so the server-side copilot block-metadata fallback can render
  model options when the providers store is not initialized.
- blocks/utils.test.ts: add litellm to mock providers state (initial
  + beforeEach reset) and add a parallel store-bucket guard test
  mirroring the vLLM case.
- providers/utils.test.ts: add parallel getApiKey test for litellm.

Author: waleedlatif1

apps/sim/blocks/utils.test.ts

@@ -27,6 +27,7 @@ const { mockProviders } = vi.hoisted(() => ({
       base: { models: [] as string[], isLoading: false },
       ollama: { models: [] as string[], isLoading: false },
       vllm: { models: [] as string[], isLoading: false },
+      litellm: { models: [] as string[], isLoading: false },
       openrouter: { models: [] as string[], isLoading: false },
       fireworks: { models: [] as string[], isLoading: false },
     },
@@ -101,6 +102,7 @@ describe('getApiKeyCondition / shouldRequireApiKeyForModel', () => {
       base: { models: [], isLoading: false },
       ollama: { models: [], isLoading: false },
       vllm: { models: [], isLoading: false },
+      litellm: { models: [], isLoading: false },
       openrouter: { models: [], isLoading: false },
       fireworks: { models: [], isLoading: false },
     }
@@ -185,6 +187,11 @@ describe('getApiKeyCondition / shouldRequireApiKeyForModel', () => {
       expect(evaluateCondition('my-custom-model')).toBe(false)
     })
 
+    it('does not require API key when model is in the LiteLLM store bucket', () => {
+      mockProviders.value.litellm.models = ['litellm/anthropic/claude-sonnet-4-6']
+      expect(evaluateCondition('litellm/anthropic/claude-sonnet-4-6')).toBe(false)
+    })
+
     it('requires API key when model is in the fireworks store bucket', () => {
       mockProviders.value.fireworks.models = ['fireworks/llama-3']
       expect(evaluateCondition('fireworks/llama-3')).toBe(true)

apps/sim/blocks/utils.ts

@@ -51,13 +51,15 @@ export function getModelOptions() {
   const baseModels = providersState.providers.base.models
   const ollamaModels = providersState.providers.ollama.models
   const vllmModels = providersState.providers.vllm.models
+  const litellmModels = providersState.providers.litellm.models
   const openrouterModels = providersState.providers.openrouter.models
   const fireworksModels = providersState.providers.fireworks.models
   const allModels = Array.from(
     new Set([
       ...baseModels,
       ...ollamaModels,
       ...vllmModels,
+      ...litellmModels,
       ...openrouterModels,
       ...fireworksModels,
     ])

apps/sim/lib/copilot/tools/server/blocks/get-blocks-metadata-tool.ts

@@ -768,6 +768,7 @@ function callOptionsWithFallback(
       base: { models: staticModels.map((m) => m.id) },
       ollama: { models: [] },
       vllm: { models: [] },
+      litellm: { models: [] },
       openrouter: { models: [] },
       fireworks: { models: [] },
     },

apps/sim/providers/utils.test.ts

@@ -168,6 +168,19 @@ describe('getApiKey', () => {
       expect(key2).toBe('user-key')
     }
   )
+
+  it.concurrent(
+    'should return empty or user-provided key for litellm provider without requiring API key',
+    () => {
+      isHostedSpy.mockReturnValue(false)
+
+      const key = getApiKey('litellm', 'litellm/anthropic/claude-sonnet-4-6')
+      expect(key).toBe('empty')
+
+      const key2 = getApiKey('litellm', 'litellm/openai/gpt-4', 'user-key')
+      expect(key2).toBe('user-key')
+    }
+  )
 })
 
 describe('Model Capabilities', () => {