feat: managed zsh config + optional installers + version bump action

.github/workflows/bump-version.yml

@@ -0,0 +1,67 @@
+name: Bump version.txt
+
+on:
+  push:
+    branches: [ "main" ]
+    # Avoid infinite loop when this workflow commits version.txt.
+    paths-ignore:
+      - "version.txt"
+
+concurrency:
+  group: bump-version-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: write
+
+jobs:
+  bump:
+    if: github.actor != 'github-actions[bot]'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Bump patch version in version.txt
+        shell: bash
+        run: |
+          set -euo pipefail
+
+          file="version.txt"
+          if [[ ! -f "$file" ]]; then
+            echo "0.0.1" > "$file"
+          else
+            v="$(tr -d '[:space:]' < "$file")"
+            if [[ "$v" =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]; then
+              major="${BASH_REMATCH[1]}"
+              minor="${BASH_REMATCH[2]}"
+              patch="${BASH_REMATCH[3]}"
+              patch="$((patch + 1))"
+              echo "${major}.${minor}.${patch}" > "$file"
+            else
+              echo "version.txt has invalid format: '$v' (expected x.y.z)" >&2
+              exit 1
+            fi
+          fi
+
+          echo "New version: $(cat "$file")"
+
+      - name: Commit and push
+        shell: bash
+        run: |
+          set -euo pipefail
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+          # If version didn't change for any reason, do nothing.
+          git add version.txt
+          if git diff --cached --quiet; then
+            echo "No changes to commit."
+            exit 0
+          fi
+
+          git commit -m "chore: bump version [skip ci]"
+          git push
+