Revert src changes; skill applies them at install time

Phase 2 of the SKILL.md already contains the Dockerfile + TOOL_ALLOWLIST
edit instructions with an "ALREADY APPLIED" short-circuit. Keeping those
edits out of trunk means users who never run /add-gmail-tool don't carry
the Gmail MCP package in their image.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

container/agent-runner/src/providers/claude.ts

@@ -55,7 +55,6 @@ const TOOL_ALLOWLIST = [
   'Skill',
   'NotebookEdit',
   'mcp__nanoclaw__*',
-  'mcp__gmail__*',
 ];
 
 interface SDKUserMessage {