Three-level code review (quick / thorough / architectural)

Review this code at three depths. Be direct.

```{{language}}
{{paste code or diff}}
```

Context:
- What this PR does: {{one sentence}}
- Who's the team / how senior: {{junior / mixed / senior}}

Output three reviews:

**Level 1: Quick** — only the things that absolutely have to change before merge (bugs, security issues, breaks tests)

**Level 2: Thorough** — code quality, naming, structure, maintainability. Things worth fixing but won't block merge.

**Level 3: Architectural** — does this code belong here? Does it suggest the abstraction is wrong? Is there a refactor brewing? Skip if not relevant.

For each comment: line number + what + why. Don't be vague. If the code is good, say so for that level rather than padding with nits.