feat: remove Claude Code provider completely

[roomote]

Closes #10645

This PR removes the Claude Code provider completely from the Roo Code extension.

Changes Made

Integration Layer

• Deleted src/integrations/claude-code/ directory including OAuth manager and streaming client
• Removed all OAuth authentication flows and token management

Type Definitions

• Removed packages/types/src/providers/claude-code.ts and associated tests
• Updated provider enums and schemas to exclude claude-code
• Removed claudeCodeModels, ClaudeCodeRateLimitInfo, and related types

API Handlers

• Deleted src/api/providers/claude-code.ts and all tests
• Removed ClaudeCodeHandler from API handler factory
• Cleaned up imports and references in provider index files

Core Extension

• Removed Claude Code OAuth initialization from extension.ts
• Deleted claudeCodeSignIn, claudeCodeSignOut, and requestClaudeCodeRateLimits message handlers
• Removed Claude Code authentication state from webview state

UI Components

• Deleted ClaudeCode.tsx and ClaudeCodeRateLimitDashboard.tsx components
• Updated ApiOptions.tsx to remove Claude Code-specific rendering
• Removed claudeCodeIsAuthenticated from extension state
• Updated constants and provider lists

Translations

• Removed Claude Code-related i18n keys from all locale files (18 languages)
• Cleaned up authentication error messages

Configuration

• Kept migration code for claudeCodeLegacySettingsMigrated to handle existing user configs
• Removed Claude Code from ANTHROPIC_STYLE_PROVIDERS
• Updated checkExistApiConfig to exclude claude-code from special cases

Testing

CI/CD will run full test suite. Removed files:

• 11 source files (~4,000+ lines of code)
• 4 test files

[roomote]

Rooviewer   See task on Roo Cloud

The PR successfully removes the claude-code provider source files, but several test files outside the diff still reference the removed provider. These will cause test failures and need to be updated.

Issues Found:

• packages/types/src/__tests__/provider-settings.test.ts (lines 10-13): Test case "should return 'anthropic' for claude-code provider" tests getApiProtocol("claude-code") which will now return "openai" instead of "anthropic" since claude-code was removed from ANTHROPIC_STYLE_PROVIDERS
• webview-ui/src/components/ui/hooks/__tests__/useSelectedModel.spec.ts (lines 415-484): Contains entire describe block "claude-code provider" that tests apiProvider: "claude-code" which is no longer a valid ProviderName
• src/core/config/__tests__/importExport.spec.ts (multiple locations): References claude-code provider in mock implementations (lines 71-78), test case for reasoning budget fields (lines 484-547), and parameterized tests (lines 1721-1791)

_{Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.}