docs: add pre-release section and link ArtifactHub annotations

Document how the action handles pre-release tags (-rc pattern),
including the prerelease annotation and skipped changelog generation.
Link "ArtifactHub annotations" to the official documentation.

Co-authored-by: Copilot <copilot@github.com>

README.md

@@ -1,6 +1,8 @@
 # ah-annotation
 
-GitHub Action to generate ArtifactHub changelog annotations from Git commit history and add them to `Chart.yaml`.
+GitHub Action to generate [ArtifactHub
+annotations](https://artifacthub.io/docs/topics/annotations/helm/#supported-annotations) from Git commit history and add
+them to `Chart.yaml`.
 
 The action parses conventional commit messages between two Git tags and produces an `artifacthub.io/changes` annotation.
 Pre-release tags (matching `-rc`) are detected automatically and result in an `artifacthub.io/prerelease` annotation
@@ -17,7 +19,7 @@ steps:
   - uses: actions/checkout@v7.0.1
     with:
       fetch-depth: 0
-  - uses: volker.raschek/ah-annotations@v0.0.1
+  - uses: volker.raschek/ah-annotations@v0.1.1
 ```
 
 ### Explicit tags
@@ -29,7 +31,7 @@ steps:
   - uses: actions/checkout@v7.0.1
     with:
       fetch-depth: 0
-  - uses: volker.raschek/ah-annotations@v0.0.1
+  - uses: volker.raschek/ah-annotations@v0.1.1
     with:
       old-tag: v1.0.0
       new-tag: v2.0.0
@@ -38,16 +40,33 @@ steps:
 ## Inputs
 
 | Name               | Required | Default                              | Description                                |
-| --------- | -------- | ------------- | ------------------------------------ |
+| ------------------ | -------- | ------------------------------------ | ------------------------------------------ |
+| `chart-path`       | no       | `${{ github.workspace }}/Chart.yaml` | Path to the Helm chart file.               |
 | `old-tag`          | no       | auto-detected                        | Start tag for changelog generation.        |
 | `new-tag`          | no       | auto-detected                        | End tag for changelog generation.          |
+| `yq-version`       | no       | `v4.44.6`                            | Version of yq to install.                  |
+| `yq-arch`          | no       | auto-detected                        | Architecture of yq binary to download.     |
+| `yq-os`            | no       | auto-detected                        | Operating system of yq binary to download. |
+| `yq-binary-name`   | no       | `yq`                                 | Name of the yq binary to download.         |
+| `yq-download-url`  | no       | auto-built                           | Full URL to download yq from.              |
 
 ## Requirements
 
 - The repository must be checked out with full history (`fetch-depth: 0`).
-- A `Chart.yaml` file must exist in the working directory.
+- A `Chart.yaml` file must exist at the path specified by `chart-path`.
 - Commit messages must follow the [Conventional Commits](https://www.conventionalcommits.org/) format.
 
+## Pre-releases
+
+Tags matching the pattern `-rc` (e.g. `v1.0.0-rc.1`, `v2.0.0-rc`) are treated as pre-releases.
+When `new-tag` is a pre-release tag, the action:
+
+1. Sets `artifacthub.io/prerelease: "true"` in `Chart.yaml`.
+2. Skips changelog generation entirely.
+
+When auto-detecting tags (no explicit `old-tag`/`new-tag`), the action ignores pre-release tags and selects the two
+most recent stable tags instead.
+
 ## Commit type mapping
 
 | Commit type                                      | ArtifactHub kind |

action.yaml

@@ -2,6 +2,10 @@ name: "ArtifactHub Annotations"
 description: "Generate ArtifactHub changelog annotations from git commit history and add them to Chart.yaml"
 
 inputs:
+  chart-path:
+    description: "Path to the Helm chart file"
+    default: "${{ github.workspace }}/Chart.yaml"
+    required: false
   old-tag:
     description: "Start tag for changelog generation. If not set, auto-detected from git tags."
     required: false
@@ -49,7 +53,7 @@ runs:
     - name: Add ArtifactHub annotations
       shell: bash
       env:
+        CHART_FILE: ${{ inputs.chart-path }}
         INPUT_OLD_TAG: ${{ inputs.old-tag }}
         INPUT_NEW_TAG: ${{ inputs.new-tag }}
       run: "${GITHUB_ACTION_PATH}/add-annotations.sh"
-

add-annotations.sh

@@ -6,7 +6,7 @@
 
 set -euo pipefail
 
-readonly CHART_FILE="Chart.yaml"
+readonly CHART_FILE="${CHART_FILE:="Chart.yaml"}"
 readonly RC_PATTERN="\-rc([-\.][0-9]+)?$"
 
 CHANGE_LOG_YAML=""

install-yq.sh

@@ -78,5 +78,5 @@ echo "INFO: Installed ${yq_installed_version} in ${bin_path}"
 
 # Ensure yq is in PATH for subsequent steps
 if [[ -n "${GITHUB_PATH:-}" ]]; then
-  echo "$(dirname "${bin_path}")" >> "${GITHUB_PATH}"
+  dirname "${bin_path}" >> "${GITHUB_PATH}"
 fi

renovate.json

@@ -31,6 +31,18 @@
       "depNameTemplate": "actions/checkout",
       "datasourceTemplate": "github-releases",
       "versioningTemplate": "semver"
+    },
+    {
+      "customType": "regex",
+      "fileMatch": [
+        "^README\\.md$"
+      ],
+      "matchStrings": [
+        "`(?<currentValue>[^\\s\"']+)`"
+      ],
+      "depNameTemplate": "mikefarah/yq",
+      "datasourceTemplate": "github-releases",
+      "versioningTemplate": "semver"
     }
   ],
   "packageRules": [