fix: use ANTHROPIC_AUTH_TOKEN instead of ANTHROPIC_API_KEY to prevent login prompt (#2)

Claude Code checks ANTHROPIC_AUTH_TOKEN to determine if the user is
authenticated. Previously we were setting ANTHROPIC_API_KEY which
Claude Code ignores, causing it to show a login prompt even though
the proxy was running correctly.

Now setting ANTHROPIC_AUTH_TOKEN to a placeholder value since the
proxy handles authentication via x402/wallet signature.

Author: 0xCheetah1

src/commands/start.ts

@@ -171,8 +171,7 @@ function launchServer(
         env: {
           ...cleanEnv,
           ANTHROPIC_BASE_URL: `http://localhost:${port}/api`,
-          ANTHROPIC_API_KEY:
-            'sk-ant-api03-brcc-proxy-00000000000000000000000000000000000000000000-00000000000000',
+          ANTHROPIC_AUTH_TOKEN: 'x402-proxy-handles-auth',
           ANTHROPIC_DEFAULT_SONNET_MODEL: sonnetModel,
           ANTHROPIC_DEFAULT_OPUS_MODEL: opusModel,
           ANTHROPIC_DEFAULT_HAIKU_MODEL: haikuModel,