feat: add get-repo-name (#20)

Reviewed-on: #20
Co-authored-by: Timo Behrendt <t.behrendt@t00n.de>
Co-committed-by: Timo Behrendt <t.behrendt@t00n.de>

get-repo-name/README.md

@@ -0,0 +1,11 @@
+# get-repo-name
+
+Outputs the repository name from the Git/Gitea/GitHub environment without the owner.
+
+Example: `t.behrendt/actions` → `actions`
+
+```yaml
+- id: repo
+  uses: https://gitea.t000-n.de/t.behrendt/actions/get-repo-name@0.0.0
+- run: echo "Repository name is ${{ steps.repo.outputs.name }}"
+```

get-repo-name/action.yaml

@@ -0,0 +1,16 @@
+name: Get repo name
+description: Outputs the repository name without the owner (e.g. "owner/repo" → "repo")
+
+outputs:
+  name:
+    description: The repository name without the owner
+    value: ${{ steps.repo-name.outputs.name }}
+
+runs:
+  using: "composite"
+  steps:
+    - id: repo-name
+      shell: bash
+      run: |
+        REPO="${GITEA_REPOSITORY:-$GITHUB_REPOSITORY}"
+        echo "name=${REPO##*/}" >> $GITHUB_OUTPUT