build(snap): add snap packaging (#1800)

Fixes #1062.

.github/workflows/publish-snap.yaml

@@ -0,0 +1,58 @@
+name: Publish Snap Package
+
+on:
+  release:
+    types: [published]
+  workflow_dispatch:
+    inputs:
+      channel:
+        description: "Snap Store channel"
+        required: true
+        default: edge
+        type: choice
+        options:
+          - stable
+          - candidate
+          - beta
+          - edge
+  # TODO: Add schedule trigger for edge channel.
+  # schedule:
+  #   - cron: '0 0 * * 1'
+
+permissions: {}
+
+concurrency:
+  group: ${{ github.workflow }}
+  cancel-in-progress: false
+
+jobs:
+  publish:
+    name: ${{ matrix.name }}
+    if: github.repository == 'zealdocs/zeal'
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: amd64
+            os: ubuntu-latest
+          - name: arm64
+            os: ubuntu-24.04-arm
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+
+      - name: Build Snap
+        id: build
+        uses: snapcore/action-build@v1
+
+      - name: Publish to Snap Store
+        uses: snapcore/action-publish@v1
+        env:
+          SNAPCRAFT_STORE_CREDENTIALS: ${{ secrets.SNAPCRAFT_STORE_CREDENTIALS }}
+        with:
+          snap: ${{ steps.build.outputs.snap }}
+          release: ${{ inputs.channel || 'stable' }}