github: allow grep in claude code review

Allow Bash(grep:*) so Claude can search the codebase for context
during PR reviews. Without this, grep calls using shell glob patterns
were denied even though plain directory greps were allowed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Link: https://github.com/openwrt/openwrt/pull/22897
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

.github/workflows/claude-code-review.yml

@@ -32,5 +32,5 @@ jobs:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           trigger_phrase: "/claude"
           claude_args: >-
-            --allowedTools "mcp__github_inline_comment__create_inline_comment"
+            --allowedTools "mcp__github_inline_comment__create_inline_comment,Bash(grep:*)"
             --disallowedTools "Bash(git add:*),Bash(git commit:*),Bash(git rm:*),Bash(git push:*)"