chore(release): update version to 1.0.81 and metadata

linux/centos/relspec.spec

@@ -1,5 +1,5 @@
 Name:           relspec
-Version:        1.0.74
+Version:        1.0.81
 Release:        1%{?dist}
 Summary:        RelSpec is a comprehensive database relations management tool that reads, transforms, and writes database table specifications across multiple formats and ORMs.
 
@@ -25,7 +25,7 @@ DBML, GraphQL, and more.
 export CGO_ENABLED=0
 go build \
     -trimpath \
-    -ldflags "-X git.warky.dev/wdevs/relspecgo/cmd/relspec.version=%{version}" \
+    -ldflags "-X 'git.warky.dev/wdevs/relspecgo/pkg/buildinfo.Version=v%{version}' -X 'git.warky.dev/wdevs/relspecgo/pkg/buildinfo.BuildDate=$(date -u +"%%Y-%%m-%%d %%H:%%M:%%S UTC")'" \
     -o %{name} ./cmd/relspec
 
 %install