fix: isolate H5 access test from ambient CLAUDE_H5_AUTO_PUBLIC_URL

The beforeEach hook saved but did not clear the env var, so tests
that expected publicBaseUrl=null got the auto-discovered LAN URL
instead when CLAUDE_H5_AUTO_PUBLIC_URL=1 was set in the environment.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/server/__tests__/h5-access-service.test.ts

@@ -27,6 +27,7 @@ beforeEach(async () => {
   originalH5PublicBaseUrl = process.env.CLAUDE_H5_PUBLIC_BASE_URL
   originalH5AutoPublicUrl = process.env.CLAUDE_H5_AUTO_PUBLIC_URL
   process.env.CLAUDE_CONFIG_DIR = tmpDir
+  delete process.env.CLAUDE_H5_AUTO_PUBLIC_URL
 })
 
 afterEach(async () => {