feat: add persistent CPU search engine and CLI with lifecycle tests

.github/workflows/ci.yml

@@ -0,0 +1,16 @@
+name: Core CI
+on: [push, pull_request]
+jobs:
+  core:
+    strategy:
+      matrix:
+        os: [windows-latest, ubuntu-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt, clippy
+      - run: cargo fmt --all -- --check
+      - run: cargo clippy --workspace --all-targets -- -D warnings
+      - run: cargo test --workspace --locked