Add terraform state registry (#36710)

Adds terraform/opentofu state registry with locking. Implements: https://github.com/go-gitea/gitea/issues/33644. I also checked [encrypted state](https://opentofu.org/docs/language/state/encryption), it works out of the box.

Docs PR: https://gitea.com/gitea/docs/pulls/357

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Co-authored-by: Andras Elso <elso.andras@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/packages/descriptor.go

@@ -212,6 +212,8 @@ func GetPackageDescriptorWithCache(ctx context.Context, pv *PackageVersion, c *c
 		metadata = &rubygems.Metadata{}
 	case TypeSwift:
 		metadata = &swift.Metadata{}
+	case TypeTerraformState:
+		// terraform packages have no metadata
 	case TypeVagrant:
 		metadata = &vagrant.Metadata{}
 	default: