Delete upstream workflows

This fork does not ship upstream's releases, and its hosted-runner jobs
never start here.

Claude-Session: https://claude.ai/code/session_01HuMDfgFssPUptYUzgZ6Cp8

.github/workflows/ci.yml

@@ -1,42 +0,0 @@
-name: CI
-
-on:
-  push:
-    branches: [main]
-  pull_request:
-    branches: [main]
-
-jobs:
-  lint:
-    runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        node-version: [24.x]
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v5
-
-      - name: Install pnpm
-        uses: pnpm/action-setup@v6
-        with:
-          version: 11.0.9
-
-      - name: Setup Node.js
-        uses: actions/setup-node@v5
-        with:
-          node-version: ${{ matrix.node-version }}
-          cache: 'pnpm'
-
-      - name: Install dependencies
-        run: pnpm install --frozen-lockfile
-
-      - name: Lint project
-        run: pnpm lint
-
-      - name: Test project
-        run: pnpm run test
-
-      - name: Check formatting
-        run: pnpm prettier --check src

.github/workflows/release.yml

@@ -1,46 +0,0 @@
-name: Release & Publish
-
-on:
-  push:
-    tags:
-      - "v*"
-
-jobs:
-  release:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-      id-token: write
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v5
-
-      - name: Install pnpm
-        uses: pnpm/action-setup@v6
-        with:
-          version: 11.0.9
-
-      - name: Setup Node.js
-        uses: actions/setup-node@v5
-        with:
-          node-version: 24.x
-          cache: pnpm
-          registry-url: https://registry.npmjs.org
-
-      - name: Update npm
-        run: npm install -g npm@latest
-
-      - name: Install dependencies
-        run: pnpm install --frozen-lockfile
-
-      - name: Build project
-        run: pnpm run build
-
-      - name: Publish to npm
-        run: pnpm publish --access public --no-git-checks
-
-      - name: Create GitHub Release
-        uses: softprops/action-gh-release@v2
-        with:
-          generate_release_notes: true