ci: pin current claude-sonnet-4-6 model in claude-code-action workflows

[MementoRC]

Summary

The anthropics/claude-code-action@beta review/assistant jobs were failing with:

API Error: 404 not_found_error model: claude-sonnet-4-20250514

The action's built-in default model (claude-sonnet-4-20250514) has been removed from the API, so any job that didn't pin a model 404'd. Both workflows only had a commented-out example (# model: "claude-opus-4-20250514", itself deprecated), so they fell back to the dead default.

Change

Pin an explicit current model in both workflows' with: blocks:

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

model: "claude-sonnet-4-6"

YAML-only change; no code or tests affected. Unblocks the Claude review bot on PRs (e.g. the failure observed on #182).

🤖 Generated with Claude Code

[github-actions]

Claude finished @MementoRC's task —— View job

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PR Review

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This is a clean, minimal fix. Here's my review:

Summary

The change pins model: "claude-sonnet-4-6" in both workflow files to replace the action's stale default (claude-sonnet-4-20250514) which was removed from the API, causing 404 errors.

Code Quality

The change is correct and well-scoped. The inline comments explaining the fix (# Pin an explicit current model; the action's old default...) are helpful for future maintainers.

Potential Issues

Model string format inconsistency — This repo uses claude-sonnet-4-6 as the model identifier, but the standard Anthropic API model naming convention uses date-based suffixes (e.g. claude-sonnet-4-20250514). The string claude-sonnet-4-6 appears to be an alias or shorthand. This works today, but aliases can be remapped over time without notice — potentially introducing drift between what you pinned and what actually runs. Consider confirming with Anthropic docs whether claude-sonnet-4-6 is a stable pinned identifier or a floating alias.

claude-code-review.yml is missing github_token — Actually it does pass it (github_token: ${{ secrets.GITHUB_TOKEN }}), so that's fine.

claude.yml doesn't pass github_token explicitly — .github/workflows/claude.yml:52-53 only passes claude_code_oauth_token. The claude-code-review.yml passes both. This asymmetry predates this PR and isn't introduced by it, but worth noting.

Security

No concerns. Secrets are referenced via ${{ secrets.* }} and never hardcoded. No new permissions are introduced.

Test Coverage

YAML-only change; no unit tests applicable. The fix is self-validating once the action runs successfully on a PR.

Verdict

Approved — The fix is correct, minimal, and well-documented. The only actionable suggestion is to verify that claude-sonnet-4-6 is a stable pinned model ID rather than a floating alias.