AI DevFlow Studio v1.3.0

Release artifact bundle for v1.3.0. The required real OpenCode provider smoke was completed as an explicit local signoff gate and is not run in CI.

Recovery provenance: these assets were produced from commit 06f3cc3 by successful pre-tag Release run 30651471798 after all required jobs passed. Tag-triggered run 30651860241 passed Windows, Postgres, and Docker, then failed before repository checkout in the artifact job because actions/checkout combined shallow fetch with annotated-tag fetching; no product build or test failed in that job.