chore(preview-v3): release 3.0.0-beta.3

[github-actions]

🤖 I have created a release beep boop

3.0.0-beta.3 (2026-06-12)

Features

• add API-coverage drift report (autogen pipeline stage 1) (#445) (13c2b21)
• add scaffold-resource workflow (autogen pipeline stage 2 v0) (#446) (3025320)
• expose max_concurrency as an optional provider attribute (preview-v3) (#450) (59ed7ad)
• scaffold Metrics (beta) resource (autogen stage 2) (#453) (3972d91)
• ship migrate-tf-syntax binaries and v3 migration guide (#448) (644e5d8)

Bug Fixes

• feature_flag: demote prereq destroy plan check to a warning (#451) (ed6e6b0)

---

This PR was generated with Release Please. See documentation.

---

Note

Low Risk
Version and changelog-only Release Please PR with no runtime code changes in the diff.

Overview
Release Please bumps the preview-v3 canary manifest from 3.0.0-beta.2 to 3.0.0-beta.3 and adds the matching CHANGELOG.md section for 2026-06-12.

The new changelog entry documents what ships in this beta (autogen API drift report and scaffold workflows, optional max_concurrency on the provider, Metrics beta scaffold, migrate-tf-syntax binaries and v3 migration guide, and demoting the feature-flag prerequisite destroy plan check to a warning). No provider or application code changes appear in this diff—only release metadata.

^{Reviewed by Cursor Bugbot for commit 2195274. Bugbot is set up for automated code reviews on this repo. Configure here.}