docs(tutorial): add Releasing with the SCM Version Provider

Author: woile

docs/tutorials/release-scm.md

@@ -0,0 +1,71 @@
+# Releasing with the SCM Version Provider
+
+## About
+
+When `version_provider` is set to `scm`, Commitizen reads the version directly from your Git tags instead of a config file.
+This provider is **read-only**: it can determine the current version, but it cannot write a new one for you.
+
+```toml title=".cz.toml"
+[tool.commitizen]
+tag_format = "v${version}"
+version_provider = "scm"
+```
+
+This means `cz bump` cannot complete its usual job of writing the new version anywhere (see [Why can't I bump with SCM?](#why-cant-i-bump-with-scm) below).
+
+## Creating a New Version Tag Manually
+
+To release a new version without an extra commit, compute the next tag yourself and create it directly:
+
+```sh
+next_version=$(cz version --project --next --tag)
+git tag --annotate "$next_version" --message "$next_version"
+git push --follow-tags
+```
+
+!!! tip
+    Wrap this in a CI job to fully automate releases when using the `scm` provider using [setup-cz](github.com/commitizen-tools/setup-cz)
+
+## Why Can't I Bump with SCM?
+
+When you run `cz bump`, Commitizen normally creates a new commit that updates the version somewhere,
+either in `.cz.toml`, or in `pyproject.toml` if you're using Python, or `Cargo.toml` for rust.
+It may also update `version_files` and regenerate `CHANGELOG.md`.
+
+Commitizen deliberately bundles a new release into a single commit.
+This is core to its philosophy: the version should live in the code itself, not only in a Git tag,
+so anyone can read the current version straight from the source, without needing to inspect the tags.
+When a Git tag is the sole source of truth, that guarantee disappears,
+the version becomes metadata layered on top of your history instead of something visible within the code itself.
+
+## Github action example
+
+```yaml title=".github/workflows/bump-version.yml"
+name: Bump version
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  bump:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      actions: write
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          token: "${{ secrets.PERSONAL_ACCESS_TOKEN }}"
+          fetch-depth: 0
+          fetch-tags: true
+      - uses: commitizen-tools/setup-cz@main
+        with:
+          python-version: "3.x"
+      - id: bump-version
+        run: |
+          next_version=$(cz version --project --next --tag)
+          git tag --annotate "$next_version" --message "$next_version"
+          git push --follow-tags
+```

mkdocs.yml

@@ -70,6 +70,7 @@ nav:
     - Jenkins pipeline: "tutorials/jenkins_pipeline.md"
     - Developmental releases: "tutorials/dev_releases.md"
     - Monorepo support: "tutorials/monorepo_guidance.md"
+    - Release with SCM Version Provider: "tutorials/release-scm.md"
   - FAQ: "faq.md"
   - "features_wont_add.md"
   - Exit Codes: "exit_codes.md"