sdk-v1.21.1

Fixes

• Skill name validation at runtime — The SDK now validates skill names against a strict pattern (alphanumeric, underscore, dash) at runtime, catching invalid names early with clear error messages instead of allowing them to fail at install time.
• Skill install options validation — The SDK validates that install options are a plain object, rejecting null, arrays, or primitives with structured errors. Prevents silent failures and malformed installations.
• Table tool documented in Node README — The SDK README now lists superdoc_table in the AI tool catalog, making it discoverable for developers building AI integrations.