* fix(llm/providers/claude): attach cache_control to system block, not top-level
The Anthropic Messages API does not accept `cache_control` as a top-level
request parameter — it is a per-content-block field. Passing it at the top
level raises `TypeError` in the Python SDK (which validates kwargs against
`messages.create()`'s signature) or a `400 unknown_parameter` from the API,
so every ClaudeProvider.generate() call fails.
Move `cache_control: {"type": "ephemeral"}` onto the last system-prompt
block so ephemeral prompt caching still works when a system prompt is
present, and drop it when there isn't one (nothing to cache).
Existing tests didn't catch this because `FakeMessages.create(**_params)`
accepted anything and ignored the kwargs. FakeMessages now records
`last_params`, and two regression tests assert that:
- `cache_control` never appears as a top-level param, and
- when a system prompt is set, `cache_control` rides on the last block.
Fixes#2512
* test(claude_provider): split composite isinstance+truthiness assertion (PT018)
Ruff PT018 flagged the combined `isinstance(system, list) and system` check
in `test_generate_does_not_pass_cache_control_as_top_level_param`. Split
it into two focused asserts (`isinstance(system, list)` then `assert system`)
so a failure points at the exact violation instead of a compound condition.
Behavior unchanged; 6/6 tests still pass.
Addresses CodeRabbit review on #2515.
- add Vite and Redis pattern skills from closed stale PRs
- add frontend-slides support assets
- port skill-comply runner fixes and LLM prompt/provider regressions
- harden agent frontmatter validation and sync catalog counts
