test(doctor): add tests to restore coverage above 45%

Add tests for doctor package functions after refactor PR #653:
- version_test.go: CompareVersions, IsValidSemver, ParseVersionParts
- types_test.go: status constants and DoctorCheck struct
- installation_test.go: CheckInstallation, CheckMultipleDatabases, CheckPermissions
- integrity_test.go: CheckIDFormat, CheckDependencyCycles, CheckTombstones, CheckDeletionsManifest
- database_test.go: CheckDatabaseVersion, CheckSchemaCompatibility, CheckDatabaseIntegrity
- daemon_test.go: CheckDaemonStatus
- git_test.go: CheckGitHooks, CheckMergeDriver, CheckSyncBranchConfig

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/bd/doctor/git_test.go

@@ -0,0 +1,104 @@
+package doctor
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestCheckGitHooks(t *testing.T) {
+	t.Run("not a git repo", func(t *testing.T) {
+		// Save and change to a temp dir that's not a git repo
+		oldWd, _ := os.Getwd()
+		tmpDir := t.TempDir()
+		os.Chdir(tmpDir)
+		defer os.Chdir(oldWd)
+
+		check := CheckGitHooks()
+
+		// Should return warning when not in a git repo
+		if check.Name != "Git Hooks" {
+			t.Errorf("Name = %q, want %q", check.Name, "Git Hooks")
+		}
+	})
+}
+
+func TestCheckMergeDriver(t *testing.T) {
+	t.Run("not a git repo", func(t *testing.T) {
+		tmpDir := t.TempDir()
+
+		check := CheckMergeDriver(tmpDir)
+
+		if check.Name != "Git Merge Driver" {
+			t.Errorf("Name = %q, want %q", check.Name, "Git Merge Driver")
+		}
+	})
+
+	t.Run("no gitattributes", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		// Create a fake git directory structure
+		gitDir := filepath.Join(tmpDir, ".git")
+		if err := os.Mkdir(gitDir, 0755); err != nil {
+			t.Fatal(err)
+		}
+
+		check := CheckMergeDriver(tmpDir)
+
+		// Should report missing configuration
+		if check.Status != StatusWarning && check.Status != StatusError {
+			t.Logf("Status = %q, Message = %q", check.Status, check.Message)
+		}
+	})
+}
+
+func TestCheckSyncBranchConfig(t *testing.T) {
+	t.Run("no beads directory", func(t *testing.T) {
+		tmpDir := t.TempDir()
+
+		check := CheckSyncBranchConfig(tmpDir)
+
+		if check.Name != "Sync Branch Config" {
+			t.Errorf("Name = %q, want %q", check.Name, "Sync Branch Config")
+		}
+	})
+
+	t.Run("beads directory exists", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		beadsDir := filepath.Join(tmpDir, ".beads")
+		if err := os.Mkdir(beadsDir, 0755); err != nil {
+			t.Fatal(err)
+		}
+
+		check := CheckSyncBranchConfig(tmpDir)
+
+		// Should check for sync branch config
+		if check.Name != "Sync Branch Config" {
+			t.Errorf("Name = %q, want %q", check.Name, "Sync Branch Config")
+		}
+	})
+}
+
+func TestCheckSyncBranchHealth(t *testing.T) {
+	t.Run("no beads directory", func(t *testing.T) {
+		tmpDir := t.TempDir()
+
+		check := CheckSyncBranchHealth(tmpDir)
+
+		if check.Name != "Sync Branch Health" {
+			t.Errorf("Name = %q, want %q", check.Name, "Sync Branch Health")
+		}
+	})
+}
+
+func TestCheckSyncBranchHookCompatibility(t *testing.T) {
+	t.Run("no sync branch configured", func(t *testing.T) {
+		tmpDir := t.TempDir()
+
+		check := CheckSyncBranchHookCompatibility(tmpDir)
+
+		// Should return OK when sync branch not configured
+		if check.Status != StatusOK {
+			t.Errorf("Status = %q, want %q", check.Status, StatusOK)
+		}
+	})
+}