ci: reuse shared notification and AI review workflows

[zhongkechen]

Summary

• replace the local AI review implementation with the SHA-pinned reusable workflow from aws/aws-durable-execution-ci while retaining the Python-specific prompt
• consolidate pull request, issue, and release Slack notifications into one shared workflow caller
• decouple release notifications from PyPI publication and remove duplicated AI review support files

Testing

• /tmp/actionlint-v1.7.12/actionlint .github/workflows/*.yml
• hatch run python .github/scripts/lintcommit.py

[github-actions]

Codex AI review

No actionable findings. Residual risk is limited to runtime environment, secret, OIDC, and Slack routing behavior in the externally pinned reusable workflows.

Reviewed commit 6571f04295dff255280fdb14a54b3b8d083bb408. Workflow run

[github-actions]

Claude AI review

No blocking findings. This PR is a clean CI refactor that replaces local AI-review/notification implementations with SHA-pinned reusable workflows and removes the now-dead support files. Deletions are internally consistent: the notify-release job and its ./.github/workflows/notify-release.yml reference are removed together, and none of the deleted scripts/schema (run_claude_isolated.sh, prepare_ai_review_context.sh, prepare_ai_review_user.sh, post_ai_review_summary.sh, ai-pr-review-schema.json) are referenced elsewhere after the change. The prompt-path target (.github/prompts/ai-pr-review.md) still exists, and both reusable-workflow callers pin the same commit SHA.

Residual risk (not verifiable from this repository — the behavior now lives entirely in the external aws/aws-durable-execution-ci reusable workflows):

• Draft-PR Slack notifications (.github/workflows/notify.yml:19). The old notify-pr.yml gated on if: github.event.pull_request.draft == false, but the new caller passes opened/reopened/ready_for_review straight through with no draft guard. If the shared notify.yml does not re-implement that filter, opening a draft PR will now send a Slack notification — a behavior change from the base branch. Confirm the shared workflow filters drafts.

• AI-review gating (.github/workflows/ai-pr-review.yml:64). The removed approve_review job explicitly gated dependabot, drafts, and fork PRs before running under ai-pr-review-runtime; this is now fully delegated to the shared workflow. Confirm the shared workflow preserves the same fork/draft/dependabot approval boundary given pull_request_target exposes secrets.

• Concurrency (.github/workflows/ai-pr-review.yml). The concurrency group with cancel-in-progress: true was dropped. Since the trigger still includes synchronize, rapid pushes may now run overlapping reviews unless the shared workflow defines its own concurrency group.

• Release notification decoupling (.github/workflows/pypi-publish.yml). Release notifications now fire on release: published independent of PyPI publish success (previously gated on needs.pypi-publish.result == 'success'). This matches the PR's stated intent; flagged only so it's an acknowledged behavior change.

No test changes are expected for a workflow-only refactor; the real coverage depends on the pinned external workflows, which cannot be inspected here.

Reviewed commit 6571f04295dff255280fdb14a54b3b8d083bb408. Workflow run