chore(release): 0.13.0 (#88)

Bumps all twelve workspace packages to 0.13.0 and moves the otel entry
from [Unreleased] into a dated 0.13.0 section.

Also republishes @vymalo/opencode-otel with provenance. 0.12.0 went out
via a local `npm publish`, which cannot generate a SLSA attestation —
that version is on npm, functional and signed, but unattested, and npm
does not allow republishing over an existing version. Publishing 0.13.0
through publish.yml restores parity with the rest of the suite.

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>