Skill tool fails immediately when invoking code-review plugin (Execute skill error, ~24ms)

## Describe the bug

When `code-review@claude-code-plugins` is configured as a plugin, the plugin installs successfully and appears correctly in the skill list, but the `Skill` tool call fails immediately (~24ms) with a generic error. Claude then falls back to performing the review inline without the plugin.

## Environment

- **Claude Code version**: 2.1.90
- **claude-code-action**: `anthropics/claude-code-action@v1` (SHA: `58dbe8ed6879f0d3b02ac295b20d5fdfe7733e0c`)
- **Session ID**: `b27886c8-78cf-4530-aafe-930f542ef645`
- **Trigger**: `issue_comment`

## Steps to reproduce

1. Configure the workflow with `code-review@claude-code-plugins` plugin (see workflow below).
2. Trigger via PR comment (`@claude please review this PR`).
3. Plugin installs and is listed in skills correctly.
4. Claude invokes `Skill` tool with `{ "skill": "code-review:code-review", "args": "--comment" }`.
5. Tool returns `is_error: true` after ~24ms.

## What happens

From the session log (`show_full_output: true`):

```
✔ Successfully installed plugin: code-review@claude-code-plugins (scope: user)
...
"skills": ["code-review:code-review", ...] ← plugin registered correctly
...
# Claude invokes Skill tool:
{ "name": "Skill", "input": { "skill": "code-review:code-review", "args": "--comment" } }

# Immediate failure (~24ms later):
{ "type": "tool_result", "content": "Execute skill: code-review:code-review", "is_error": true }
"tool_use_result": "Error: Execute skill: code-review:code-review"
```

The error message is just the execution command echoed back with no stack trace or detail, suggesting an unhandled exception in the skill execution layer.

## Expected behavior

The `code-review:code-review` skill executes and performs the review using the plugin's logic.

## Actual behavior

Skill tool fails immediately. Claude falls back to performing an inline review without the plugin.

## Workflow config

```yaml
- uses: anthropics/claude-code-action@v1
with:
claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
github_token: ${{ secrets.GITHUB_TOKEN }}
plugin_marketplaces: https://github.com/anthropics/claude-code.git
plugins: code-review@claude-code-plugins
claude_args: >-
--allowedTools Read,Write,Edit,Bash(git:*),
mcp__github_inline_comment__create_inline_comment,
Bash(gh pr comment:*),Bash(gh pr diff:*),Bash(gh pr view:*)
prompt: |
If asked to review code or a pull request, you MUST use `/code-review:code-review --comment`.
```

## Notes

- The `rate_limit_event` (`overageStatus: rejected`) fires at the same timestamp but is unrelated — `status: allowed` confirms the request went through.
- Related but different issue: #1087 (plugin completes but posts no comment — different failure mode).
- Plugin path on runner: `/home/runner/.claude/plugins/marketplaces/claude-code-plugins/plugins/code-review`

Start at the Skill tool invocation and the claude-code-action workflow configuration, using the provided session log and the plugin path on the runner to trace the immediate execution failure. Reproduce with code-review@claude-code-plugins and confirm that code-review:code-review executes successfully and performs the review instead of falling back inline.

Written by the indexing model from the issue text.