workflows: add nsolid release automation

.github/nsolid-release-lines.json

@@ -0,0 +1,3 @@
+{
+  "nodeReleaseLines": [22, 24]
+}

.github/workflows/create-nsolid-release-proposal.yml

@@ -0,0 +1,48 @@
+name: Create N|Solid Release Proposal
+
+on:
+  workflow_dispatch:
+    inputs:
+      node-line:
+        required: true
+        type: choice
+        options:
+          - '22'
+          - '24'
+        description: Node.js release line
+
+concurrency: ${{ github.workflow }}-${{ inputs.node-line }}
+
+permissions:
+  contents: write
+  issues: write
+  pull-requests: write
+
+jobs:
+  create:
+    if: github.repository == 'nodesource/nsolid'
+    runs-on: ubuntu-slim
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+        with:
+          fetch-depth: 0
+          persist-credentials: true
+          token: ${{ secrets.GH_USER_TOKEN || github.token }}
+
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020  # v4.4.0
+        with:
+          node-version: lts/*
+
+      - name: Create release proposal
+        run: tools/actions/create-nsolid-release-proposal.sh
+        env:
+          GITHUB_TOKEN: ${{ secrets.GH_USER_TOKEN || github.token }}
+          GH_TOKEN: ${{ secrets.GH_USER_TOKEN || github.token }}
+          NODE_LINE: ${{ inputs.node-line }}
+
+      - name: Upload conflict report
+        if: failure() && hashFiles('nsolid-release-conflicts.md') != ''
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02  # v4.6.2
+        with:
+          name: nsolid-release-conflicts
+          path: nsolid-release-conflicts.md

.github/workflows/watch-node-releases.yml

@@ -0,0 +1,29 @@
+name: Watch Node.js Releases
+
+on:
+  schedule:
+    - cron: '17 12 * * *'
+  workflow_dispatch:
+
+concurrency: ${{ github.workflow }}
+
+permissions:
+  contents: write
+  issues: write
+  pull-requests: write
+
+jobs:
+  watch:
+    if: github.repository == 'nodesource/nsolid'
+    runs-on: ubuntu-slim
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020  # v4.4.0
+        with:
+          node-version: lts/*
+
+      - name: Watch Node.js release lines
+        run: node tools/actions/watch-node-releases.mjs
+        env:
+          GITHUB_TOKEN: ${{ secrets.GH_USER_TOKEN || github.token }}

doc/contributing/nsolid-release-automation.md

@@ -0,0 +1,103 @@
+# N|Solid release automation
+
+This document describes the GitHub Actions automation that tracks Node.js
+releases and prepares N|Solid release proposal pull requests.
+
+The automation is intentionally small. A releaser should be able to run it from
+the GitHub Actions UI by selecting only the Node.js release line.
+
+## What it does
+
+The automation has two workflows:
+
+* `Watch Node.js Releases`
+  * runs on a schedule and can also be started manually;
+  * reads `.github/nsolid-release-lines.json`;
+  * checks the latest stable Node.js release for each configured line;
+  * skips the release if an N|Solid release branch or tag already exists;
+  * creates or reuses a tracking issue;
+  * attempts to create the release proposal.
+* `Create N|Solid Release Proposal`
+  * is manually started with one input: `node-line`;
+  * finds the latest stable Node.js tag for that line;
+  * checks out `node-v<line>.x-nsolid-v6.x`;
+  * reads the current N|Solid version from `src/node_version.h`;
+  * creates `node-vX.Y.Z-nsolid-vA.B.C-release`;
+  * merges the upstream Node.js tag;
+  * sets `NSOLID_VERSION_IS_RELEASE` to `1`;
+  * prepends the N|Solid changelog entry;
+  * pushes the release branch;
+  * opens a draft release PR.
+
+If the Node.js tag merge conflicts, the workflow stops, comments on the
+tracking issue when one exists, and uploads `nsolid-release-conflicts.md` as an
+artifact.
+
+The automation does not create a release tag. Release tags should still be
+created by the releaser after the proposal is reviewed.
+
+## Supported release lines
+
+The supported lines are configured in `.github/nsolid-release-lines.json`:
+
+```json
+{
+  "nodeReleaseLines": [22, 24]
+}
+```
+
+Only lines listed there are watched by the scheduled workflow and shown in the
+manual workflow selector.
+
+## Add a release line
+
+When N|Solid starts supporting a new Node.js release line:
+
+1. Add the major version to `.github/nsolid-release-lines.json`.
+2. Add the same value to the `node-line` options in
+   `.github/workflows/create-nsolid-release-proposal.yml`.
+3. Ensure the base branch exists:
+   `node-v<line>.x-nsolid-v6.x`.
+4. Ensure the N|Solid changelog exists:
+   `doc/changelogs/NSOLID_CHANGELOG_V6_NODE_V<line>.md`.
+5. Run the workflow manually once for that line.
+
+For example, to add Node.js v26 support, add `26` to the JSON file and add
+`'26'` to the workflow options.
+
+## Remove a release line
+
+When N|Solid stops supporting a Node.js release line:
+
+1. Remove the major version from `.github/nsolid-release-lines.json`.
+2. Remove the same value from the `node-line` options in
+   `.github/workflows/create-nsolid-release-proposal.yml`.
+
+Do not delete existing release branches, tags, or changelog files as part of
+removing the line from automation.
+
+## Manual use
+
+To prepare a release proposal manually:
+
+1. Open the `Create N|Solid Release Proposal` workflow.
+2. Select the Node.js release line.
+3. Run the workflow.
+
+The workflow always uses the latest stable Node.js release for the selected
+line. If a different upstream tag is required, prepare the release manually.
+
+## Failure handling
+
+If the release branch already exists and has an open PR, the workflow reuses the
+existing PR. If the release branch exists without an open PR, the workflow fails
+so a releaser can inspect the branch before opening a PR manually.
+
+If the workflow fails with merge conflicts:
+
+1. Open the workflow artifact named `nsolid-release-conflicts`.
+2. Resolve the listed conflicts locally from the generated release branch steps.
+3. Continue the release manually.
+
+If the workflow fails while creating the PR, the release branch may already have
+been pushed. Open the PR manually using the branch named in the workflow logs.