actions) add gitea-compatible checkout action

action.yml

@@ -0,0 +1,81 @@
+name: 'Checkout'
+description: 'Checkout a repository in Gitea Actions environments'
+author: 'CampbellWireless'
+
+inputs:
+  repository:
+    description: 'Repository in owner/name format'
+    required: false
+    default: ${{ github.repository }}
+  ref:
+    description: 'The branch, tag, or SHA to checkout'
+    required: false
+    default: ${{ github.sha }}
+  token:
+    description: 'Token used to authenticate fetch operations'
+    required: false
+    default: ${{ secrets.GITHUB_TOKEN }}
+  server-url:
+    description: 'Base URL of the Git server (include subpath if applicable)'
+    required: true
+  path:
+    description: 'Relative path under GITHUB_WORKSPACE to checkout into'
+    required: false
+    default: '.'
+  fetch-depth:
+    description: 'Number of commits to fetch. Use 0 for full history.'
+    required: false
+    default: '1'
+
+outputs:
+  commit:
+    description: 'Checked out commit SHA'
+    value: ${{ steps.checkout.outputs.commit }}
+
+runs:
+  using: 'composite'
+  steps:
+    - id: checkout
+      shell: bash
+      run: |
+        set -euo pipefail
+
+        workspace="${GITHUB_WORKSPACE:-$(pwd)}"
+        target_path="${{ inputs.path }}"
+        if [[ "$target_path" == "." ]]; then
+          repo_dir="$workspace"
+        else
+          repo_dir="$workspace/$target_path"
+          mkdir -p "$repo_dir"
+        fi
+
+        repo_url="${{ inputs.server-url }}"
+        repo_url="${repo_url%/}/${{ inputs.repository }}.git"
+
+        if [[ ! -d "$repo_dir/.git" ]]; then
+          git init "$repo_dir"
+        fi
+
+        git -C "$repo_dir" remote remove origin >/dev/null 2>&1 || true
+        git -C "$repo_dir" remote add origin "$repo_url"
+
+        token='${{ inputs.token }}'
+        if [[ -n "$token" ]]; then
+          auth="$(printf '%s' "${GITHUB_ACTOR:-x-access-token}:$token" | base64 | tr -d '\n')"
+          host="$(printf '%s' '${{ inputs.server-url }}' | sed -E 's#https?://([^/]+).*#\1#')"
+          git -C "$repo_dir" config --local "http.https://$host/.extraheader" "AUTHORIZATION: basic $auth"
+        fi
+
+        depth='${{ inputs.fetch-depth }}'
+        if [[ "$depth" == "0" ]]; then
+          git -C "$repo_dir" fetch --prune --no-recurse-submodules origin \
+            +refs/heads/*:refs/remotes/origin/* \
+            +refs/tags/*:refs/tags/*
+          git -C "$repo_dir" checkout --detach "${{ inputs.ref }}"
+        else
+          git -C "$repo_dir" fetch --prune --no-recurse-submodules --depth "$depth" origin "${{ inputs.ref }}"
+          git -C "$repo_dir" checkout --detach FETCH_HEAD
+        fi
+
+        commit_sha="$(git -C "$repo_dir" rev-parse HEAD)"
+        echo "commit=$commit_sha" >> "$GITHUB_OUTPUT"