feat(skills): support paths in Claude Code skills

[jornetsimon]

No description provided.

[dyoshikawa-claw]

This is a clean, well-tested addition. The schema, conversion, and round-trip all follow the existing patterns for allowed-tools, model, and disable-model-invocation exactly. Test coverage is thorough — string form, array form, validation rejects, and round-trip preservation are all covered.

One small thing: the fromDir method at line 201–225 already handles paths correctly since it delegates to the schema — but no test explicitly exercises importing a SKILL.md from disk with a paths field. The existing round-trip and conversion tests give good confidence, though.

Otherwise, looks good to merge.

[dyoshikawa-claw]

Clean addition that follows the existing patterns well. The schema, both conversion directions, and the rulesync type are all updated consistently. The test coverage for string/array variants in object conversion and round-trip is thorough.

Two things to consider adding:

• A fromDir test for paths, similar to the existing should load skill with model test, so that YAML parsing of comma-separated strings vs arrays is covered through the I/O path too.
• A test that combines paths with another claudecode field like model or allowed-tools, to verify they don't interfere with each other during the spread-based conversion.

[dyoshikawa-claw]

In claudecode-rule.ts, paths accepts only string[], while here it accepts string | string[]. A brief comment explaining this difference would help future maintainers understand it is intentional, not an oversight.