test: repair test suite after R1-R3 refactors and add Claude Code tests

The R1-R3 refactors removed the per-provider handle*Error methods,
consolidated validators into validateNumberInRange, renamed Gemini's
buildGenerationConfig to buildConfig, and split OpenWebUI's message
conversion and response formatting into openwebui-strategies.ts.
44 of 91 existing tests broke as a result.

Changes:

claude.test.ts (8 -> 13 passing)
- Switch error mapping tests from handleAnthropicError to the base
  normalizeError method.
- Update temperature error-message expectation to match the new
  validateNumberInRange wording.

openai.test.ts (16 -> 22 passing)
- Same handleOpenAIError -> normalizeError switch.
- Add a regression test for the 429+"quota" path that goes through
  mapProviderError instead of the base mapping.

gemini.test.ts (17 -> 27 passing)
- Update getInfo expectations to the new default model (gemini-2.5)
  and provider version 2.0.0.
- Switch to normalizeError.
- Rename buildGenerationConfig -> buildConfig (renamed during R2).
- Update formatCompletionResponse mocks: the @google/genai SDK
  exposes response.text as a getter rather than walking
  candidates[0].content.parts.

openwebui.test.ts (4 -> 19 passing)
- Drop tests for convertMessages / convertMessagesToPrompt /
  formatChatResponse / formatOllamaResponse / makeRequest: these
  moved into openwebui-strategies.ts and openwebui-http.ts during R3
  and warrant their own test files.
- Add error-mapping tests covering the new mapProviderError +
  providerErrorMessages plumbing.

claude-code.test.ts (new, 18 tests)
- Constructor accepts subscription mode (empty config).
- getInfo advertises subscriptionAuth + requiresLocalCli.
- mapProviderError catches ENOENT and "not logged in".
- errorForSdkAssistantError covers each documented SDK error code.
- buildPrompt handles single-turn pass-through, multi-system
  combination, multi-turn flattening with role labels, and rejects
  empty turn lists.

Full suite: 100 pass / 0 fail across 5 files.

tests/claude-code.test.ts

@@ -0,0 +1,178 @@
+/**
+ * Tests for ClaudeCodeProvider
+ *
+ * The provider shells out to the local Claude Code CLI via
+ * @anthropic-ai/claude-agent-sdk. Tests cover the public surface and the
+ * provider-specific hooks; full integration is not exercised because it
+ * would spawn a real CLI process.
+ */
+
+import { describe, it, expect, beforeEach } from 'bun:test';
+import { ClaudeCodeProvider } from '../src/providers/claude-code.js';
+import { AIProviderError, AIErrorType } from '../src/types/index.js';
+
+describe('ClaudeCodeProvider', () => {
+  let provider: ClaudeCodeProvider;
+
+  beforeEach(() => {
+    provider = new ClaudeCodeProvider({ apiKey: 'test-key' });
+  });
+
+  describe('Constructor', () => {
+    it('should accept empty config (subscription mode)', () => {
+      const p = new ClaudeCodeProvider({});
+      expect(p).toBeInstanceOf(ClaudeCodeProvider);
+    });
+
+    it('should accept apiKey override', () => {
+      const p = new ClaudeCodeProvider({ apiKey: 'sk-...' });
+      expect(p).toBeInstanceOf(ClaudeCodeProvider);
+    });
+
+    it('should accept custom defaults', () => {
+      const p = new ClaudeCodeProvider({
+        defaultModel: 'opus',
+        maxTurns: 5,
+        allowedTools: ['Read', 'Bash'],
+        cwd: '/tmp/agent'
+      });
+      expect(p).toBeInstanceOf(ClaudeCodeProvider);
+    });
+
+    it('should reject non-string apiKey', () => {
+      expect(() => new ClaudeCodeProvider({ apiKey: 123 as any }))
+        .toThrow(AIProviderError);
+    });
+  });
+
+  describe('getInfo', () => {
+    it('should advertise subscriptionAuth capability', () => {
+      const info = provider.getInfo();
+
+      expect(info.name).toBe('Claude Code');
+      expect(info.supportsStreaming).toBe(true);
+      expect(info.capabilities).toMatchObject({
+        subscriptionAuth: true,
+        requiresLocalCli: true,
+        systemMessages: true
+      });
+      expect(info.models).toContain('sonnet');
+      expect(info.models).toContain('opus');
+    });
+  });
+
+  describe('Error mapping', () => {
+    const mapError = (err: any) => (provider as any).mapProviderError(err);
+
+    it('should detect missing CLI', () => {
+      const err = new Error('spawn claude ENOENT');
+
+      const mapped = mapError(err);
+
+      expect(mapped).toBeInstanceOf(AIProviderError);
+      expect(mapped.type).toBe(AIErrorType.INVALID_REQUEST);
+      expect(mapped.message).toContain('CLI');
+    });
+
+    it('should detect missing authentication', () => {
+      const err = new Error('not logged in');
+
+      const mapped = mapError(err);
+
+      expect(mapped).toBeInstanceOf(AIProviderError);
+      expect(mapped.type).toBe(AIErrorType.AUTHENTICATION);
+    });
+
+    it('should return null for unrelated errors', () => {
+      expect(mapError(new Error('something else'))).toBeNull();
+    });
+  });
+
+  describe('SDK assistant error mapping', () => {
+    const mapSdkError = (code: string) => (provider as any).errorForSdkAssistantError(code);
+
+    it('should map authentication_failed', () => {
+      const err = mapSdkError('authentication_failed');
+      expect(err.type).toBe(AIErrorType.AUTHENTICATION);
+    });
+
+    it('should map rate_limit', () => {
+      const err = mapSdkError('rate_limit');
+      expect(err.type).toBe(AIErrorType.RATE_LIMIT);
+    });
+
+    it('should map model_not_found', () => {
+      const err = mapSdkError('model_not_found');
+      expect(err.type).toBe(AIErrorType.MODEL_NOT_FOUND);
+    });
+
+    it('should map server_error to NETWORK', () => {
+      const err = mapSdkError('server_error');
+      expect(err.type).toBe(AIErrorType.NETWORK);
+    });
+
+    it('should fall back to UNKNOWN for unrecognized codes', () => {
+      const err = mapSdkError('weird_new_code');
+      expect(err.type).toBe(AIErrorType.UNKNOWN);
+    });
+  });
+
+  describe('Prompt building', () => {
+    const build = (messages: any[]) => (provider as any).buildPrompt(messages);
+
+    it('should pass single user turn through unchanged', () => {
+      const result = build([{ role: 'user', content: 'Hello' }]);
+
+      expect(result.prompt).toBe('Hello');
+      expect(result.systemPrompt).toBeUndefined();
+    });
+
+    it('should combine multiple system messages', () => {
+      const result = build([
+        { role: 'system', content: 'Be brief' },
+        { role: 'system', content: 'Use British spelling' },
+        { role: 'user', content: 'Hi' }
+      ]);
+
+      expect(result.systemPrompt).toBe('Be brief\n\nUse British spelling');
+      expect(result.prompt).toBe('Hi');
+    });
+
+    it('should flatten multi-turn conversation with role labels', () => {
+      const result = build([
+        { role: 'user', content: 'What is 2+2?' },
+        { role: 'assistant', content: '4' },
+        { role: 'user', content: 'Why?' }
+      ]);
+
+      expect(result.prompt).toContain('Human: What is 2+2?');
+      expect(result.prompt).toContain('Assistant: 4');
+      expect(result.prompt).toContain('Human: Why?');
+      expect(result.prompt.endsWith('Assistant:')).toBe(true);
+    });
+
+    it('should reject empty turn list', () => {
+      expect(() => build([{ role: 'system', content: 'only system' }]))
+        .toThrow(AIProviderError);
+    });
+  });
+
+  describe('Validation', () => {
+    it('should require initialization before complete()', async () => {
+      await expect(
+        provider.complete({ messages: [{ role: 'user', content: 'test' }] })
+      ).rejects.toThrow('Provider must be initialized before use');
+    });
+
+    it('should validate temperature range when initialized', async () => {
+      (provider as any).initialized = true;
+
+      await expect(
+        provider.complete({
+          messages: [{ role: 'user', content: 'test' }],
+          temperature: 1.5
+        })
+      ).rejects.toThrow(/temperature must be at most 1/);
+    });
+  });
+});