Merge main into development: idempotency guard for release-crates, updated SKILL.md

Brings the two post-release fixes forward so the next release cycle branches from a tree that matches main: - .github/workflows/release-crates.yml: dispatch-distributions now skips when the GitHub release for the tag already exists, so a late or duplicate tag-push trigger can't re-build the binaries or re-publish the MCP server. - .agents/skills/ascapi-release/SKILL.md: bumped to v1.2, documents release-crates.yml as the default flow, and calls out the observed missed-trigger failure mode with the manual dispatch command to recover. - .github/workflows/release-github.yml: unchanged from development's version (already had the concurrency block). main now matches.