feat: enable GitHub inline comment server for code-review plugin

Add support for automatically including the GitHub inline comment server when
the code-review@claude-code-plugins plugin is specified in the plugins input.
This enables the code-review plugin to post inline comments on PRs even in
agent mode.

Changes:
- Parse plugins input as string[] in parseGitHubContext
- Update inline comment server logic to check for code-review plugin
- Add comprehensive test coverage for inline comment server detection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

action.yml

@@ -167,6 +167,7 @@ runs:
         ADDITIONAL_PERMISSIONS: ${{ inputs.additional_permissions }}
         CLAUDE_ARGS: ${{ inputs.claude_args }}
         ALL_INPUTS: ${{ toJson(inputs) }}
+        PLUGINS: ${{ inputs.plugins }}
 
     - name: Install Base Action Dependencies
       if: steps.prepare.outputs.contains_trigger == 'true'