fix: resolve all golangci-lint errors

- errcheck: explicitly discard error returns for git config --unset
- gosec G304: add nolint for safe file read from hardcoded list
- gosec G306: add nolint for .gitattributes (must be world-readable)
- unparam: remove unused gitDir param, use _ for unused ctx
- unparam: change functions with always-nil error returns to void

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

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

cmd/bd/init.go

@@ -426,10 +426,7 @@ With --stealth: configures global git settings for invisible beads usage:
 		// Add "landing the plane" instructions to AGENTS.md and @AGENTS.md
 		// Skip in stealth mode (user wants invisible setup) and quiet mode (suppress all output)
 		if !stealth {
-			if err := addLandingThePlaneInstructions(!quiet); err != nil && !quiet {
-				yellow := color.New(color.FgYellow).SprintFunc()
-				fmt.Fprintf(os.Stderr, "%s Failed to add landing-the-plane instructions: %v\n", yellow("⚠"), err)
-			}
+			addLandingThePlaneInstructions(!quiet)
 		}
 
 		// Skip output if quiet mode
@@ -1590,7 +1587,7 @@ const landingThePlaneSection = `
 `
 
 // addLandingThePlaneInstructions adds "landing the plane" instructions to AGENTS.md and @AGENTS.md
-func addLandingThePlaneInstructions(verbose bool) error {
+func addLandingThePlaneInstructions(verbose bool) {
 	// Files to update (AGENTS.md and @AGENTS.md for web Claude)
 	agentFiles := []string{"AGENTS.md", "@AGENTS.md"}
 
@@ -1602,13 +1599,12 @@ func addLandingThePlaneInstructions(verbose bool) error {
 			}
 		}
 	}
-
-	return nil
 }
 
 // updateAgentFile creates or updates an agent instructions file with landing the plane section
 func updateAgentFile(filename string, verbose bool) error {
 	// Check if file exists
+	//nolint:gosec // G304: filename comes from hardcoded list in addLandingThePlaneInstructions
 	content, err := os.ReadFile(filename)
 	if os.IsNotExist(err) {
 		// File doesn't exist - create it with basic structure

cmd/bd/reset.go

@@ -227,7 +227,7 @@ func showResetPreview(items []resetItem) {
 	fmt.Printf("To proceed, run: %s\n", yellow("bd reset --force"))
 }
 
-func performReset(items []resetItem, gitDir, beadsDir string) {
+func performReset(items []resetItem, _, beadsDir string) {
 	green := color.New(color.FgGreen).SprintFunc()
 
 	var errors []string
@@ -257,8 +257,8 @@ func performReset(items []resetItem, gitDir, beadsDir string) {
 
 		case "config":
 			// Remove merge driver config (ignore errors - may not exist)
-			exec.Command("git", "config", "--unset", "merge.beads.driver").Run()
-			exec.Command("git", "config", "--unset", "merge.beads.name").Run()
+			_ = exec.Command("git", "config", "--unset", "merge.beads.driver").Run()
+			_ = exec.Command("git", "config", "--unset", "merge.beads.name").Run()
 			if !jsonOutput {
 				fmt.Printf("%s Removed merge driver config\n", green("✓"))
 			}
@@ -363,5 +363,6 @@ func removeGitattributesEntry() error {
 
 	// Add single trailing newline
 	newContent += "\n"
+	//nolint:gosec // G306: .gitattributes must be world-readable (0644)
 	return os.WriteFile(".gitattributes", []byte(newContent), 0644)
 }

cmd/bd/sync.go

@@ -90,10 +90,7 @@ Use --merge to merge the sync branch back to main branch.`,
 
 		// If check mode, run pre-sync integrity checks (bd-hlsw.1)
 		if checkIntegrity {
-			if err := showSyncIntegrityCheck(ctx, jsonlPath); err != nil {
-				fmt.Fprintf(os.Stderr, "Error: %v\n", err)
-				os.Exit(1)
-			}
+			showSyncIntegrityCheck(ctx, jsonlPath)
 			return
 		}
 
@@ -836,7 +833,7 @@ func gitHasChanges(ctx context.Context, filePath string) (bool, error) {
 
 // getRepoRootForWorktree returns the main repository root for running git commands
 // This is always the main repository root, never the worktree root
-func getRepoRootForWorktree(ctx context.Context) string {
+func getRepoRootForWorktree(_ context.Context) string {
 	repoRoot, err := git.GetMainRepoRoot()
 	if err != nil {
 		// Fallback to current directory if GetMainRepoRoot fails
@@ -1797,7 +1794,8 @@ type OrphanedChildren struct {
 
 // showSyncIntegrityCheck performs pre-sync integrity checks without modifying state.
 // bd-hlsw.1: Detects forced pushes, prefix mismatches, and orphaned children.
-func showSyncIntegrityCheck(ctx context.Context, jsonlPath string) error {
+// Exits with code 1 if problems are detected.
+func showSyncIntegrityCheck(ctx context.Context, jsonlPath string) {
 	fmt.Println("Sync Integrity Check")
 	fmt.Println("====================")
 
@@ -1858,8 +1856,6 @@ func showSyncIntegrityCheck(ctx context.Context, jsonlPath string) error {
 		data, _ := json.MarshalIndent(result, "", "  ")
 		fmt.Println(string(data))
 	}
-
-	return nil
 }
 
 // checkForcedPush detects if the sync branch has diverged from remote.