fix: resolve model config provider via ai_provider_id (#26660)

-  `site/src/pages/AISettingsPage/ProvidersPage/components/providerFormApiMap.ts`):
`providerFormValuesToCreate` returns `type: "bedrock"` when the form
type is `bedrock`, instead of `type: "anthropic"` with Bedrock settings.
- Updated `providerFormApiMap.test.ts` to expect `type:
"bedrock"` and `MockAIProviderBedrock` fixture in `entities.ts` to
`type: "bedrock"`. Added Bedrock fixtures to `ModelsPageView` stories
asserting the AWS Bedrock icon renders correctly.

Refs: [CODAGT-549](https://linear.app/codercom/issue/CODAGT-549/bedrock-models-use-anthropic-styling-and-icons)

> 🤖

site/src/pages/AISettingsPage/ModelsPage/ModelsPageView.stories.tsx

@@ -5,7 +5,9 @@ import type { ChatModelConfig } from "#/api/typesGenerated";
 import ModelsPageView from "./ModelsPageView";
 import {
 	MockAnthropicProviderState,
+	MockBedrockProviderState,
 	MockOpenAIProviderState,
+	mockBedrockClaude,
 	mockClaude,
 	mockDisabledModel,
 	mockGPT5,
@@ -17,8 +19,12 @@ const meta: Meta<typeof ModelsPageView> = {
 	args: {
 		isLoading: false,
 		error: null,
-		models: [mockGPT5, mockClaude, mockDisabledModel],
-		providerStates: [MockOpenAIProviderState, MockAnthropicProviderState],
+		models: [mockGPT5, mockClaude, mockDisabledModel, mockBedrockClaude],
+		providerStates: [
+			MockOpenAIProviderState,
+			MockAnthropicProviderState,
+			MockBedrockProviderState,
+		],
 	},
 	parameters: {
 		reactRouter: reactRouterParameters({
@@ -45,6 +51,12 @@ export const Default: Story = {
 		await expect(canvas.getByText("Claude Sonnet 4.5")).toBeInTheDocument();
 		await expect(canvas.getAllByText("OpenAI").length).toBeGreaterThan(0);
 		await expect(canvas.getByText("Anthropic")).toBeInTheDocument();
+		await expect(
+			canvas.getByText("Claude Sonnet 4.5 (Bedrock)"),
+		).toBeInTheDocument();
+		await expect(canvas.getByText("AWS Bedrock")).toBeInTheDocument();
+		// The Bedrock model config should render the Bedrock provider icon.
+		await expect(canvas.getByAltText("AWS Bedrock")).toBeInTheDocument();
 		await expect(canvas.getAllByText("Enabled").length).toBeGreaterThan(0);
 		await expect(canvas.getByText("Default")).toBeInTheDocument();
 		await expect(canvas.getByText("Disabled")).toBeInTheDocument();

site/src/pages/AISettingsPage/ModelsPage/testFixtures.ts

@@ -83,6 +83,31 @@ export const MockAnthropicProviderState: ProviderState = {
 	modelConfigs: [mockClaude],
 };
 
+const MockBedrockProviderConfig: ChatProviderConfig = {
+	...MockOpenAIProviderConfig,
+	id: "prov-bedrock",
+	provider: "bedrock",
+	display_name: "AWS Bedrock",
+};
+
+export const mockBedrockClaude: ChatModelConfig = {
+	...mockClaude,
+	id: "model-bedrock-claude",
+	provider: "bedrock",
+	ai_provider_id: "prov-bedrock",
+	model: "anthropic.claude-sonnet-4-5",
+	display_name: "Claude Sonnet 4.5 (Bedrock)",
+};
+
+export const MockBedrockProviderState: ProviderState = {
+	...MockOpenAIProviderState,
+	key: "prov-bedrock",
+	provider: "bedrock",
+	label: "AWS Bedrock",
+	providerConfig: MockBedrockProviderConfig,
+	modelConfigs: [mockBedrockClaude],
+};
+
 export const MockCopilotProviderState: ProviderState = {
 	...MockOpenAIProviderState,
 	key: "prov-copilot",

site/src/pages/AISettingsPage/ProvidersPage/components/providerFormApiMap.test.ts

@@ -139,8 +139,12 @@ describe("parseBedrockRegionFromBaseUrl", () => {
 });
 
 describe("isBedrockProvider", () => {
-	it("recognises a discriminated bedrock provider", () => {
-		expect(isBedrockProvider(MockAIProviderBedrock)).toBe(true);
+	it("recognises a legacy bedrock provider stored as type=anthropic", () => {
+		const provider: AIProvider = {
+			...MockAIProviderBedrock,
+			type: "anthropic",
+		};
+		expect(isBedrockProvider(provider)).toBe(true);
 	});
 
 	it("recognises a provider with explicit bedrock type", () => {
@@ -332,9 +336,9 @@ describe("providerFormValuesToCreate", () => {
 	});
 
 	describe("Bedrock", () => {
-		it('maps Bedrock to a wire `type:"anthropic"`', () => {
+		it('maps Bedrock to a wire `type:"bedrock"`', () => {
 			const req = providerFormValuesToCreate(baseBedrockFormValues);
-			expect(req.type).toBe("anthropic");
+			expect(req.type).toBe("bedrock");
 		});
 
 		it("derives the region from a canonical AWS URL", () => {
@@ -669,10 +673,10 @@ describe("aiProviderToFormValues", () => {
 		expect(values.smallFastModel).toBe("anthropic.claude-haiku-4-5");
 	});
 
-	it("seeds Bedrock form values from an explicit Bedrock provider type", () => {
+	it("seeds Bedrock form values from a legacy anthropic-typed provider", () => {
 		const provider: AIProvider = {
 			...MockAIProviderBedrock,
-			type: "bedrock",
+			type: "anthropic",
 		};
 		const values = aiProviderToFormValues(provider);
 		expect(values.type).toBe("bedrock");
@@ -723,12 +727,12 @@ describe("aiProviderToFormValues", () => {
 
 	it("handles a Bedrock provider whose settings are null", () => {
 		// `isBedrockProvider` will return false, so the provider falls
-		// through to the anthropic branch. The helper must not throw.
+		// through to the generic branch. The helper must not throw.
 		const provider: AIProvider = {
 			...MockAIProviderBedrock,
 			settings: null as unknown as AIProvider["settings"],
 		};
 		const values = aiProviderToFormValues(provider);
-		expect(values.type).toBe("anthropic");
+		expect(values.type).toBe("bedrock");
 	});
 });

site/src/pages/AISettingsPage/ProvidersPage/components/providerFormApiMap.ts

@@ -146,7 +146,7 @@ export const providerFormValuesToCreate = (
 			values.roleArn.trim(),
 		);
 		return {
-			type: "anthropic",
+			type: "bedrock",
 			...base,
 			settings: settings as AIProviderSettings,
 		};

site/src/testHelpers/entities.ts

@@ -5574,13 +5574,14 @@ export const MockAIProviderAnthropic: TypesGen.AIProvider = {
 };
 
 /**
- * Bedrock providers come over the wire with `type: "anthropic"` and a
- * `settings._type: "bedrock"` discriminator. `isBedrockProvider` and the
- * backend (see `coderd/ai_providers.go`) enforce this convention.
+ * Bedrock providers come over the wire with `type: "bedrock"` and a
+ * `settings._type: "bedrock"` discriminator. `isBedrockProvider` checks
+ * both the type and the settings discriminator, and also accepts legacy
+ * providers stored as `type: "anthropic"` with Bedrock settings.
  */
 export const MockAIProviderBedrock: TypesGen.AIProvider = {
 	id: "9c2e3b41-2e9f-4c97-9a4f-2e1a3d8f9f21",
-	type: "anthropic",
+	type: "bedrock",
 	name: "bedrock",
 	display_name: "Bedrock",
 	base_url: "https://bedrock-runtime.us-east-2.amazonaws.com",