Remove GitHub workflows

.github/workflows/validate.yml

@@ -1,29 +0,0 @@
-name: validate
-
-on:
-  push:
-    branches: [main]
-  pull_request:
-    branches: [main]
-
-jobs:
-  validate:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-
-      - name: Install nono
-        run: |
-          brew tap guybedford/nono
-          brew install nono
-
-      - name: Validate profile
-        run: nono profile validate opencode-tinfoil
-
-      - name: Set up Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: '1.22'
-
-      - name: Build TUI
-        run: cd tui && go build -buildvcs=false ./...