#11313: feat(ci): add staged release pipeline workflows (dormant)

## Summary **Part 1 of 2** — split from #10755 for safe, additive-only merge. Adds all new CI/CD workflow files for the staged branch promotion pipeline (`develop → alpha → beta → main`). **All push triggers are intentionally disabled** — workflows use `workflow_dispatch` or `workflow_call` only. No existing workflows are modified. ### What's included | Workflow | Trigger | Purpose | |---|---|---| | `feature-pr.yml` | `workflow_dispatch` (push disabled) | Auto-create PRs to develop | | `hotfix-pr.yml` | `workflow_dispatch` (push disabled) | Emergency hotfix PRs to main | | `promote-branch.yml` | `workflow_dispatch` (push disabled) | Staged branch promotion | | `release-orchestrator.yml` | `workflow_call` (push disabled) | Release pipeline | | `deployment-strategy.yml` | `workflow_call` | npm + Docker deployment | | `testing-strategy.yml` | `workflow_call` | Progressive test gates | | `generate-changelog.yml` | `workflow_call` | Auto-generate changelogs | | `version-operations.yml` | `workflow_call` | Version bumping | | `release.yml` | `workflow_dispatch` | Manual release trigger | | `rollback.yml` | `workflow_dispatch` | Emergency rollback | | `discord-notify` action | Reusable action | Discord notifications | ### What's NOT included (deferred to PR 2) - **No changes to `ci.yml`** — Windows and macOS tests continue to run on every PR as today - **No push triggers** — nothing fires automatically on push to any branch - Push triggers and `ci.yml` modifications will be activated in a follow-up PR (#TBD) when the `develop`/`alpha`/`beta` branches are set up ### Also - `docs/reference/pipeline.md` — pipeline documentation - `CONTRIBUTING.md` — adds branch strategy section (clearly marked as "not yet active"), Core vs ClawHub guidance, and maintainer credit ### Testing All new workflows are inert (no push triggers). Merging this has zero effect on existing CI behavior. <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR adds a set of new, currently-dormant GitHub Actions workflows for a staged promotion/release pipeline (develop → alpha → beta → main), plus a reusable `discord-notify` composite action and accompanying documentation updates. The overall structure is additive and self-contained, but several of the new workflows/actions would fail immediately when invoked: the testing strategy attempts to call `ci.yml` as a reusable workflow even though `ci.yml` is not `workflow_call`-enabled; the deployment strategy workflow contains an invalid duplicate step entry in the `docker-arm64` job; and the Discord notification composite action’s jq invocation uses `--argjson` with quoted/non-JSON values, which will cause jq to error before sending notifications. <h3>Confidence Score: 2/5</h3> - Not safe to merge as-is because key workflows/actions will fail when triggered. - The PR is additive, but multiple introduced CI components are currently non-functional (reusable workflow call to non-reusable `ci.yml`, invalid YAML in deployment workflow, and jq argument handling that breaks Discord notifications). These are deterministic failures that will block the pipeline once activated or manually run. - .github/workflows/testing-strategy.yml, .github/workflows/deployment-strategy.yml, .github/actions/discord-notify/action.yml <!-- greptile_other_comments_section --> _{(4/5) You can add custom instructions or style guidelines for the agent [here](https://app.greptile.com/review/github)!} <!-- /greptile_comment -->