improvements

- Consolidate status reads
- Pre-allocate descriptors
- Add read_only disk label
- Remove dead stdin field
- Guard nil pool maps
- Add error-path tests
- Add go vet to flake

flake.nix

@@ -17,6 +17,28 @@
 			default = pve-local-exporter;
 		});
 
+		checks = forAllSystems (system: let
+			pkgs = nixpkgs.legacyPackages.${system};
+			pkg = self.packages.${system}.pve-local-exporter;
+		in {
+			vet = pkgs.runCommand "go-vet" {
+				nativeBuildInputs = [ pkgs.go ];
+				inherit (pkg) src goModules;
+				CGO_ENABLED = 0;
+			} ''
+				export HOME=$TMPDIR
+				export GOPATH=$TMPDIR/go
+				workdir=$TMPDIR/src
+				mkdir -p $workdir
+				cp -r $src/* $workdir/
+				chmod -R u+w $workdir
+				ln -s $goModules $workdir/vendor
+				cd $workdir
+				go vet -mod=vendor ./...
+				touch $out
+			'';
+		});
+
 		devShells = forAllSystems (system: let
 			pkgs = nixpkgs.legacyPackages.${system};
 		in {