chore: align internal.Version sentinel to 0.0.0 (workflow#764) (#20)

ldflag injects real version at release; sentinel was 'dev' but workflow#762 standardizes on '0.0.0' so wfctl plugin validate-contract --for-publish can ParseSemver it without a special case.

Author: intel352

internal/plugin.go

@@ -8,7 +8,7 @@ import (
 
 // Version is set at build time via -ldflags
 // "-X github.com/GoCodeAlone/workflow-plugin-github/internal.Version=X.Y.Z"
-var Version = "dev"
+var Version = "0.0.0"
 
 // webhookRouteConfig is the config fragment YAML that declares the GitHub
 // webhook HTTP route so the engine's HTTP server registers it via the normal