CI: add scheduled releases + mirror workflow

* .github/workflows/release.yml:
 Add scheduled releases jobs of `$(git rev-parse --abbrev-ref HEAD)` to create
 master.zip which contains everything in the root (e.g., `./*`) of the file dir.

* .github/workflows/mirror.yml:
 Add scheduled mirroring jobs to CI.
 Mirror to all private repos via SSH.

Also move `.github/FUNDING.yml` to `workflows/` dir.

Signed-off-by: Sharp-tailed Grouse <sharptail@riseup.net>

.github/workflows/mirror.yml

@@ -0,0 +1,43 @@
+name: Mirrors
+
+# Push to all private (configured) mirrors.
+
+on: [ push, create, delete ]
+
+concurrency:
+  group: git-mirror
+
+jobs:
+  gitlab:
+    runs-on: ubuntu-latest
+    steps:
+      - name: GitLab
+        uses: wearerequired/git-mirror-action@v1
+        env:
+          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
+        with:
+          source-repo: "git@github.com:Anon-Planet/thgtoa.git"
+          destination-repo: "git@gitlab.com:{{ secrets.GITLAB_REPO_USERNAME }}/thgtoa.git"
+
+  codeberg:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Codeberg
+        uses: wearerequired/git-mirror-action@v1
+        env:
+          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
+        with:
+          source-repo: "git@github.com:Anon-Planet/thgtoa.git"
+          destination-repo: "git@codeberg.org:{{ secrets.CODEBERG_REPO_USERNAME }}/thgtoa.git"
+
+  disroot:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Disroot
+        uses: wearerequired/git-mirror-action@v1
+        env:
+          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
+        with:
+          source-repo: "git@github.com:Anon-Planet/thgtoa.git"
+          destination-repo: "git@git.disroot.org:{{ secrets.DISROOT_REPO_USERNAME }}/thgtoa.git"
+

.github/workflows/release.yml

@@ -0,0 +1,29 @@
+on:
+  push:
+    tags:
+      - "v*"
+
+jobs:
+  upload-files:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        include:
+          - name: "THGTOA"
+            branch: "master"
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          ref: ${{ matrix.branch }}
+
+      - name: Scheduled Release
+        run: |
+          zip -rv ${{ matrix.name }}.zip _site
+
+      - uses: softprops/action-gh-release@v1
+        if: startsWith(github.ref, 'refs/tags/')
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          files: |
+            ${{ matrix.name }}.zip