ci: automated versioning and publishing (#181)

> [!IMPORTANT]  
> **This change impacts how pull requests should be titled and merged**.
See below for details.

This changeset looks to resolve the issue that we have seen crop up over
the past few weeks where changes have been merged into `master` but
because a bunch of manual steps haven't been completed, new releases
(docker images) haven't been published.

For the workflows in this pull request to work correctly, one new
variable and two new secrets need to be created:

| Type | Name | Notes |
| ------------------ | ------------------ | ------------------ |
| Variable | DOCKERHUB_USERNAME | The username/account of the Docker Hub
profile under which images built should be published. |
| Secret | DOCKERHUB_TOKEN | The [access
token](https://docs.docker.com/security/for-developers/access-tokens/)
to be used to authenticate to Docker Hub. |
| Secret | GH_ACCESS_TOKEN | The GitHub access token to be used. This is
required because GitHub blocks commits created by actions spawning other
actions when using the default workflow token. |

The secrets and variable can be created from within the repository
*Settings > Secrets and variables -> Actions*.

## Pull Requests

This change introduces a dependency on [conventional commit
messages](https://kapeli.com/cheat_sheets/Conventional_Commits.docset/Contents/Resources/Documents/index#:~:text=Commits%20MUST%20be%20prefixed%20with%20a%20type%2C%20which,commit%20represents%20a%20bug%20fix%20for%20your%20application).
The action within the versioning workflow looks at the format of the
commit message to determine which of the *major*, *minor*, or *patch*
numbers to increment.

Setting pull request titles to be in conventional commit format (like
this one) and with the below pull request settings configured will
ensure that the versioning works as expected:


![image](https://github.com/user-attachments/assets/238927ca-be57-472f-8443-26d0c174217e)

Reviewers of PRs for the project should ensure that pull request titles
are appropriate for the changes included.

Closes #147, Closes #180

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

.github/workflows/publish.yml

@@ -0,0 +1,42 @@
+name: Publish image
+on:
+  push:
+    tags: 
+      - '*'
+
+jobs:
+  publish-app:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Login to Docker Hub
+      uses: docker/login-action@v3
+      with:
+        username: ${{ vars.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+    - name: Extract metadata for the Docker image
+      id: meta
+      uses: docker/metadata-action@v5
+      with:
+        images: ${{ vars.DOCKERHUB_USERNAME }}/christmas-community
+        context: git
+        tags: |
+          type=semver,pattern={{version}}
+          type=semver,pattern={{major}}.{{minor}}
+
+    - name: Set up QEMU
+      uses: docker/setup-qemu-action@v3
+
+    - name: Set up Docker Buildx    
+      uses: docker/setup-buildx-action@v3
+
+    - name: Build and push
+      uses: docker/build-push-action@v6
+      with:
+        platforms: linux/amd64,linux/arm64
+        push: true
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}

.github/workflows/version.yml

@@ -0,0 +1,29 @@
+name: Bump version
+on:
+  push:
+    branches:
+      - master
+    paths-ignore:
+      - 'package.json'
+      - 'README.md'
+
+jobs:
+  version-app:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+      with:
+        token: ${{ secrets.GH_TOKEN_ACTION }}
+
+    - name: Bump version and push tag
+      id: changelog
+      uses: TriPSs/conventional-changelog-action@v6
+      with:
+        github-token: "${{ secrets.GH_TOKEN_ACTION }}"
+        git-user-name: "github-actions[bot]"
+        git-user-email: "github-actions[bot]@users.noreply.github.com"
+        preset: "conventionalcommits"
+        output-file: false
+        # skip-on-empty: false # good for testing
+        skip-ci: false

README.md

@@ -170,10 +170,10 @@ Hi, I'm Wingy. I made this app. My website is [samwing.dev](https://samwing.dev)
 <table>
 <tr>
     <td align="center">
-        <a href="https://github.com/Wingysam">
-            <img src="https://avatars.githubusercontent.com/u/18403742?v=4" width="100;" alt="Wingysam"/>
+        <a href="https://github.com/cj13579">
+            <img src="https://avatars.githubusercontent.com/u/1965454?v=4" width="100;" alt="cj13579"/>
             <br />
-            <sub><b>Wingysam</b></sub>
+            <sub><b>cj13579</b></sub>
         </a>
     </td></tr>
 </table>
@@ -327,6 +327,13 @@ Hi, I'm Wingy. I made this app. My website is [samwing.dev](https://samwing.dev)
             <sub><b>StS82</b></sub>
         </a>
     </td>
+    <td align="center">
+        <a href="https://github.com/alyoro">
+            <img src="https://avatars.githubusercontent.com/u/43644634?v=4" width="100;" alt="alyoro"/>
+            <br />
+            <sub><b>alyoro</b></sub>
+        </a>
+    </td>
     <td align="center">
         <a href="https://github.com/toastie89">
             <img src="https://avatars.githubusercontent.com/u/19393929?v=4" width="100;" alt="toastie89"/>