feat(server): add relicario-server for pre-receive hook

- verify-commit command checks signature against devices.json
- generate-hook outputs installable pre-receive script
- Foundation for server-side enforcement

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Cargo.toml

@@ -4,4 +4,5 @@ members = [
     "crates/relicario-core",
     "crates/relicario-cli",
     "crates/relicario-wasm",
+    "crates/relicario-server",
 ]