build: support 0.14.0

Unfortunately, this has irreconcilable incompatibilities with previous
versions of zig, due to the build.zig.zon schema changes. Support for
older versions has been dropped.

.github/workflows/ci.yaml

@@ -14,14 +14,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        zig-version: ["0.13.0"]
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        zig-version: ["0.14.0"]
+        os: [macos-latest, windows-latest]
         include:
-          - zig-version: "0.12.1"
+          - zig-version: "0.14.0"
             os: ubuntu-latest
-          - zig-version: "master"
             check-format: true
+
+          - zig-version: "master"
             os: ubuntu-latest
+
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout