Feat: Build manifest on every backend build

[oshirohugo]

What this PR does / why we need it:

This PR is adding the build manifest step after every backend build. This would simplify the build process for specific architecture and make selecting specific architectures in the plugin-actions easier

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

The drawback is that in the buildAll target the manifest will be built multiple times

[xnyo]

Great work! 🙌 Just a couple of small comments

[xnyo]

Nit, unrelated: the comment above specifies "TODO: Change to sh.RunWithV once available.", it is now available, maybe we can kill two birds with one stone? 🙂

Suggested change

	// TODO: Change to sh.RunWithV once available.
	return sh.RunWith(cfg.Env, "go", args...)
	err = sh.RunWith(cfg.Env, "go", args...)
	err = sh.RunWithV(cfg.Env, "go", args...)

[xnyo]

Another comment: if we're worried about performance and we want to make sure that the manifest is generated only once, we can wrap GenerateManifestFile into a sync.OnceValue to ensure it's called only once, like so:

diff --git a/build/common.go b/build/common.go
index c104d30..40d0972 100644
--- a/build/common.go
+++ b/build/common.go
@@ -252,8 +252,7 @@ func (Build) DarwinARM64() error {
        return buildBackend(newBuildConfig("darwin", "arm64"))
 }
 
-// GenerateManifestFile generates a manifest file for plugin submissions
-func (Build) GenerateManifestFile() error {
+var generateManifestOnce = sync.OnceValue(func() error {
        config := Config{}
        config, err := beforeBuild(config)
        if err != nil {
@@ -279,6 +278,11 @@ func (Build) GenerateManifestFile() error {
                return err
        }
        return nil
+})
+
+// GenerateManifestFile generates a manifest file for plugin submissions
+func (Build) GenerateManifestFile() error {
+       return generateManifestOnce()
 }
 
 // Debug builds the debug version for the current platform.

However what we have right now is more readable and not a concern, so unless there are other issues down the line I'd keep it like this

[xnyo]

LGTM! 🚀