feat: add local skill store and targets

internal/targets/targets_test.go

@@ -0,0 +1,70 @@
+package targets
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"sgg-ai-skill-manager/internal/domain"
+)
+
+func TestInstallCreatesJunctionAndUninstallKeepsSource(t *testing.T) {
+	root := t.TempDir()
+	source := filepath.Join(root, "repo", "demo")
+	if err := os.MkdirAll(source, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(source, "SKILL.md"), []byte("# Demo\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	manager := New(map[string]Target{
+		"codex": {ID: "codex", Name: "Codex", SkillsDir: filepath.Join(root, "codex", "skills")},
+	})
+	skill := domain.SkillState{Org: "skills", Repo: "demo", LocalPath: source, InstalledTargets: map[string]domain.InstalledTarget{}}
+
+	installed, err := manager.Install(skill, "codex")
+	if err != nil {
+		t.Fatalf("Install returned error: %v", err)
+	}
+	link := filepath.Join(root, "codex", "skills", "demo")
+	if _, err := os.Stat(filepath.Join(link, "SKILL.md")); err != nil {
+		t.Fatalf("junction does not expose SKILL.md: %v", err)
+	}
+	if installed.InstalledTargets["codex"].TargetPath != source {
+		t.Fatalf("installed target = %+v", installed.InstalledTargets["codex"])
+	}
+
+	uninstalled, err := manager.Uninstall(installed, "codex")
+	if err != nil {
+		t.Fatalf("Uninstall returned error: %v", err)
+	}
+	if _, err := os.Stat(source); err != nil {
+		t.Fatalf("source should remain after uninstall: %v", err)
+	}
+	if _, err := os.Lstat(link); !os.IsNotExist(err) {
+		t.Fatalf("link should be removed, err=%v", err)
+	}
+	if _, ok := uninstalled.InstalledTargets["codex"]; ok {
+		t.Fatal("codex install record should be removed")
+	}
+}
+
+func TestInstallRejectsExistingOrdinaryDirectory(t *testing.T) {
+	root := t.TempDir()
+	source := filepath.Join(root, "repo", "demo")
+	link := filepath.Join(root, "codex", "skills", "demo")
+	if err := os.MkdirAll(source, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.MkdirAll(link, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	manager := New(map[string]Target{
+		"codex": {ID: "codex", Name: "Codex", SkillsDir: filepath.Join(root, "codex", "skills")},
+	})
+	skill := domain.SkillState{Org: "skills", Repo: "demo", LocalPath: source, InstalledTargets: map[string]domain.InstalledTarget{}}
+
+	if _, err := manager.Install(skill, "codex"); err == nil {
+		t.Fatal("Install returned nil error for ordinary directory conflict")
+	}
+}