ForgeFlow v3.0.0-alpha.1

First v3 prerelease. Adds the Antigravity bridge, adaptive thinking, deterministic multi-model routing, supply-source priority/failover, Business Team-first worker routing, and usage telemetry. CI passed on PR #115 and on the merged main commit. Live GCP acceptance verified T3 → Pi → ForgeFlow worker routing to business-team/openai-codex/gpt-6.1-sol.