Add FirePass provider support for Kimi K2.5 Turbo

- Add new 'firepass' provider type alongside anthropic, openai, openrouter
- FirePass uses Fireworks AI's endpoint for Kimi K2.5 Turbo model
- Subscription billing model ($7/week) with 256K context window
- Anthropic API compatible (uses Anthropic SDK with custom baseURL)

Changes:
- providers.ts: Add firepass detection and base URL handling
- auth.ts: Add FirePass API key management (FIREPASS_API_KEY or FIREWORKS_API_KEY)
- config.ts: Add firepassApiKey and firepass auth provider
- client.ts: Add firepass client creation with custom baseURL
- http.ts: Add firepass auth headers
- modelStrings.ts: Return Kimi K2.5 Turbo model ID for firepass
- model.ts: Add Kimi display name handling and default model logic
- modelOptions.ts: Simplified model picker for firepass (Kimi K2.5 Turbo only)
- status.tsx: Display FirePass in status bar
- login.tsx: Add FirePass option to provider selection
- FirepassLoginFlow.tsx: New component for FirePass login flow

Usage:
1. Run /login and select "FirePass"
2. Enter your Fireworks API key
3. Model picker shows Kimi K2.5 Turbo

src/utils/http.ts

@@ -11,6 +11,7 @@ import { OAUTH_BETA_HEADER } from '../constants/oauth.js'
 import {
   getAnthropicApiKey,
   getClaudeAIOAuthTokens,
+  getFirepassApiKey,
   getOpenAIApiKey,
   getOpenRouterApiKey,
   handleOAuth401Error,
@@ -100,6 +101,22 @@ export function getAuthHeaders(): AuthHeaders {
     }
   }
 
+  if (provider === 'firepass') {
+    const apiKey = getFirepassApiKey()
+    if (!apiKey) {
+      return {
+        headers: {},
+        error: 'No FirePass API key available',
+      }
+    }
+    // FirePass uses x-api-key header like Anthropic
+    return {
+      headers: {
+        'x-api-key': apiKey,
+      },
+    }
+  }
+
   if (isClaudeAISubscriber()) {
     const oauthTokens = getClaudeAIOAuthTokens()
     if (!oauthTokens?.accessToken) {