refractor(build): move builder tasks to the builder sub package. Add tests.

pkg/prebuild/builder/core.go

@@ -0,0 +1,39 @@
+// apparmor.d - Full set of apparmor profiles
+// Copyright (C) 2021-2024 Alexandre Pujol <alexandre@pujol.io>
+// SPDX-License-Identifier: GPL-2.0-only
+
+package builder
+
+import (
+	"fmt"
+
+	"github.com/roddhjav/apparmor.d/pkg/prebuild/cfg"
+)
+
+var (
+	// Build the profiles with the following directive applied
+	Builds = []Builder{}
+
+	// Available builders
+	Builders = map[string]Builder{}
+)
+
+// Main directive interface
+type Builder interface {
+	cfg.BaseInterface
+	Apply(profile string) string
+}
+
+func Register(names ...string) {
+	for _, name := range names {
+		if b, present := Builders[name]; present {
+			Builds = append(Builds, b)
+		} else {
+			panic(fmt.Sprintf("Unknown builder: %s", name))
+		}
+	}
+}
+
+func RegisterBuilder(d Builder) {
+	Builders[d.Name()] = d
+}