Fix validatePostImport false positive for legitimate deletions (bd-pg1)

The sync validation was incorrectly triggering 'data loss detected' when
issue count decreased after import, even for legitimate deletions recorded
in deletions.jsonl.

Changes:
- Modified validatePostImport to accept jsonlPath and check deletions manifest
- When issue count decreases, check if decrease is within recorded deletions
- Updated all call sites in sync.go and daemon_sync.go
- Added comprehensive tests for deletion-aware validation

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

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

cmd/bd/daemon_sync.go

@@ -550,7 +550,7 @@ func createAutoImportFunc(ctx context.Context, store storage.Storage, log daemon
 			return
 		}
 
-		if err := validatePostImport(beforeCount, afterCount); err != nil {
+		if err := validatePostImport(beforeCount, afterCount, jsonlPath); err != nil {
 			log.log("Post-import validation failed: %v", err)
 			return
 		}
@@ -743,7 +743,7 @@ func createSyncFunc(ctx context.Context, store storage.Storage, autoCommit, auto
 			return
 		}
 
-		if err := validatePostImport(beforeCount, afterCount); err != nil {
+		if err := validatePostImport(beforeCount, afterCount, jsonlPath); err != nil {
 			log.log("Post-import validation failed: %v", err)
 			return
 		}

cmd/bd/integrity.go

@@ -13,6 +13,7 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/steveyegge/beads/internal/deletions"
 	"github.com/steveyegge/beads/internal/storage"
 	"github.com/steveyegge/beads/internal/types"
 )
@@ -287,10 +288,45 @@ func checkOrphanedDeps(ctx context.Context, store storage.Storage) ([]string, er
 }
 
 // validatePostImport checks that import didn't cause data loss.
-// Returns error if issue count decreased (data loss) or nil if OK.
+// Returns error if issue count decreased unexpectedly (data loss) or nil if OK.
-func validatePostImport(before, after int) error {
+// A decrease is legitimate if it matches deletions recorded in deletions.jsonl.
+//
+// Parameters:
+//   - before: issue count in DB before import
+//   - after: issue count in DB after import
+//   - jsonlPath: path to issues.jsonl (used to locate deletions.jsonl)
+func validatePostImport(before, after int, jsonlPath string) error {
 	if after < before {
-		return fmt.Errorf("import reduced issue count: %d → %d (data loss detected!)", before, after)
+		// Count decrease - check if this matches legitimate deletions
+		decrease := before - after
+
+		// Load deletions manifest to check for legitimate deletions
+		beadsDir := filepath.Dir(jsonlPath)
+		deletionsPath := deletions.DefaultPath(beadsDir)
+		loadResult, err := deletions.LoadDeletions(deletionsPath)
+		if err != nil {
+			// If we can't load deletions, assume the worst
+			return fmt.Errorf("import reduced issue count: %d → %d (data loss detected! failed to verify deletions: %v)", before, after, err)
+		}
+
+		// If there are deletions recorded, the decrease is likely legitimate
+		// We can't perfectly match because we don't know exactly which issues
+		// were deleted in this sync cycle vs previously. But if there are ANY
+		// deletions recorded and the decrease is reasonable, allow it.
+		numDeletions := len(loadResult.Records)
+		if numDeletions > 0 && decrease <= numDeletions {
+			// Legitimate deletion - decrease is accounted for by deletions manifest
+			fmt.Fprintf(os.Stderr, "Import complete: %d → %d issues (-%d, accounted for by %d deletion(s))\n",
+				before, after, decrease, numDeletions)
+			return nil
+		}
+
+		// Decrease exceeds recorded deletions - potential data loss
+		if numDeletions > 0 {
+			return fmt.Errorf("import reduced issue count: %d → %d (-%d exceeds %d recorded deletion(s) - potential data loss!)",
+				before, after, decrease, numDeletions)
+		}
+		return fmt.Errorf("import reduced issue count: %d → %d (data loss detected! no deletions recorded)", before, after)
 	}
 	if after == before {
 		fmt.Fprintf(os.Stderr, "Import complete: no changes\n")

cmd/bd/integrity_test.go

@@ -163,22 +163,78 @@ func TestValidatePreExportSuite(t *testing.T) {
 }
 
 func TestValidatePostImport(t *testing.T) {
-	t.Run("issue count decreased fails", func(t *testing.T) {
+	t.Run("issue count decreased with no deletions fails", func(t *testing.T) {
-		err := validatePostImport(10, 5)
+		tmpDir := t.TempDir()
+		jsonlPath := filepath.Join(tmpDir, "issues.jsonl")
+		// No deletions.jsonl file exists
+		err := validatePostImport(10, 5, jsonlPath)
 		if err == nil {
-			t.Error("Expected error for decreased issue count, got nil")
+			t.Error("Expected error for decreased issue count with no deletions, got nil")
+		}
+		if err != nil && !strings.Contains(err.Error(), "no deletions recorded") {
+			t.Errorf("Expected 'no deletions recorded' error, got: %v", err)
+		}
+	})
+
+	t.Run("issue count decreased within deletion count succeeds", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		jsonlPath := filepath.Join(tmpDir, "issues.jsonl")
+		deletionsPath := filepath.Join(tmpDir, "deletions.jsonl")
+
+		// Create deletions file with 5 deletions
+		deletionsContent := `{"id":"del-1","ts":"2024-01-01T00:00:00Z","by":"test"}
+{"id":"del-2","ts":"2024-01-01T00:00:00Z","by":"test"}
+{"id":"del-3","ts":"2024-01-01T00:00:00Z","by":"test"}
+{"id":"del-4","ts":"2024-01-01T00:00:00Z","by":"test"}
+{"id":"del-5","ts":"2024-01-01T00:00:00Z","by":"test"}
+`
+		if err := os.WriteFile(deletionsPath, []byte(deletionsContent), 0600); err != nil {
+			t.Fatalf("Failed to write deletions file: %v", err)
+		}
+
+		// Decrease of 5 matches the 5 recorded deletions
+		err := validatePostImport(10, 5, jsonlPath)
+		if err != nil {
+			t.Errorf("Expected no error when decrease matches deletions, got: %v", err)
+		}
+	})
+
+	t.Run("issue count decreased exceeding deletion count fails", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		jsonlPath := filepath.Join(tmpDir, "issues.jsonl")
+		deletionsPath := filepath.Join(tmpDir, "deletions.jsonl")
+
+		// Create deletions file with only 2 deletions
+		deletionsContent := `{"id":"del-1","ts":"2024-01-01T00:00:00Z","by":"test"}
+{"id":"del-2","ts":"2024-01-01T00:00:00Z","by":"test"}
+`
+		if err := os.WriteFile(deletionsPath, []byte(deletionsContent), 0600); err != nil {
+			t.Fatalf("Failed to write deletions file: %v", err)
+		}
+
+		// Decrease of 5 exceeds the 2 recorded deletions
+		err := validatePostImport(10, 5, jsonlPath)
+		if err == nil {
+			t.Error("Expected error when decrease exceeds deletions, got nil")
+		}
+		if err != nil && !strings.Contains(err.Error(), "exceeds") {
+			t.Errorf("Expected 'exceeds' error, got: %v", err)
 		}
 	})
 
 	t.Run("issue count same succeeds", func(t *testing.T) {
-		err := validatePostImport(10, 10)
+		tmpDir := t.TempDir()
+		jsonlPath := filepath.Join(tmpDir, "issues.jsonl")
+		err := validatePostImport(10, 10, jsonlPath)
 		if err != nil {
 			t.Errorf("Expected no error for same count, got: %v", err)
 		}
 	})
 
 	t.Run("issue count increased succeeds", func(t *testing.T) {
-		err := validatePostImport(10, 15)
+		tmpDir := t.TempDir()
+		jsonlPath := filepath.Join(tmpDir, "issues.jsonl")
+		err := validatePostImport(10, 15, jsonlPath)
 		if err != nil {
 			t.Errorf("Expected no error for increased count, got: %v", err)
 		}

cmd/bd/sync.go

@@ -332,7 +332,7 @@ Use --merge to merge the sync branch back to main branch.`,
 						if err != nil {
 							fmt.Fprintf(os.Stderr, "Warning: failed to count issues after import: %v\n", err)
 						} else {
-							if err := validatePostImport(beforeCount, afterCount); err != nil {
+							if err := validatePostImport(beforeCount, afterCount, jsonlPath); err != nil {
 								fmt.Fprintf(os.Stderr, "Post-import validation failed: %v\n", err)
 								os.Exit(1)
 							}