fix: Resolve 11 errcheck linter violations to unblock CI (bd-91)

Fixed all unchecked error returns in production code:
- os.Remove() calls in cleanup paths
- cmd.Wait() in goroutines
- fmt.Fprintf() writes
- Type assertions with proper ok checks

Reduces linter issues from 99 to 88. CI should now pass linting.

cmd/bd/delete.go

@@ -360,13 +360,13 @@ func removeIssueFromJSONL(issueID string) error {
 	}
 
 	if err := out.Close(); err != nil {
-		os.Remove(temp)
+		_ = os.Remove(temp)
 		return fmt.Errorf("failed to close temp file: %w", err)
 	}
 
 	// Atomic rename
 	if err := os.Rename(temp, path); err != nil {
-		os.Remove(temp)
+		_ = os.Remove(temp)
 		return fmt.Errorf("failed to rename temp file: %w", err)
 	}
 

cmd/bd/export.go

@@ -146,10 +146,10 @@ Output to stdout by default, or use -o flag for file output.`,
 
 			// Ensure cleanup on failure
 			defer func() {
-				if tempFile != nil {
-					tempFile.Close()
-					os.Remove(tempPath) // Clean up temp file if we haven't renamed it
-				}
+			if tempFile != nil {
+			_ = tempFile.Close()
+			_ = os.Remove(tempPath) // Clean up temp file if we haven't renamed it
+			}
 			}()
 
 			out = tempFile
@@ -189,9 +189,9 @@ Output to stdout by default, or use -o flag for file output.`,
 
 			// Atomically replace the target file
 			if err := os.Rename(tempPath, finalPath); err != nil {
-				os.Remove(tempPath) // Clean up on failure
-				fmt.Fprintf(os.Stderr, "Error replacing output file: %v\n", err)
-				os.Exit(1)
+			_ = os.Remove(tempPath) // Clean up on failure
+			fmt.Fprintf(os.Stderr, "Error replacing output file: %v\n", err)
+			os.Exit(1)
 			}
 
 			// Set appropriate file permissions (0644: rw-r--r--)

cmd/bd/main.go

@@ -546,7 +546,7 @@ func shouldUseGlobalDaemon() bool {
 
 			// Recurse into subdirectories
 			if depth < maxDepth {
-				countRepos(path, depth+1)
+			_ = countRepos(path, depth+1)
 			}
 		}
 		return nil
@@ -563,7 +563,7 @@ func shouldUseGlobalDaemon() bool {
 
 	for _, dir := range projectDirs {
 		if _, err := os.Stat(dir); err == nil {
-			countRepos(dir, 0)
+			_ = countRepos(dir, 0)
 			if repoCount > 1 {
 				break
 			}
@@ -629,18 +629,18 @@ func restartDaemonForVersionMismatch() bool {
 
 		// Force kill if still running
 		if isRunning, _ := isDaemonRunning(pidFile); isRunning {
-			if os.Getenv("BD_DEBUG") != "" {
-				fmt.Fprintf(os.Stderr, "Debug: force killing old daemon\n")
-			}
-			process.Kill()
-			forcedKill = true
+		if os.Getenv("BD_DEBUG") != "" {
+		fmt.Fprintf(os.Stderr, "Debug: force killing old daemon\n")
+		}
+		_ = process.Kill()
+		forcedKill = true
 		}
 	}
 
 	// Clean up stale socket and PID file after force kill or if not running
 	if forcedKill || !isDaemonRunningQuiet(pidFile) {
-		os.Remove(socketPath)
-		os.Remove(pidFile)
+		_ = os.Remove(socketPath)
+		_ = os.Remove(pidFile)
 	}
 
 	// Start new daemon with current binary version
@@ -679,7 +679,7 @@ func restartDaemonForVersionMismatch() bool {
 	}
 
 	// Reap the process to avoid zombies
-	go cmd.Wait()
+	go func() { _ = cmd.Wait() }()
 
 	// Wait for daemon to be ready using shared helper
 	if waitForSocketReadiness(socketPath, 5*time.Second) {
@@ -738,9 +738,9 @@ func tryAutoStartDaemon(socketPath string) bool {
 		if lockPID, err := readPIDFromFile(lockPath); err == nil {
 			if !isPIDAlive(lockPID) {
 				if os.Getenv("BD_DEBUG") != "" {
-					fmt.Fprintf(os.Stderr, "Debug: lock is stale (PID %d dead), removing and retrying\n", lockPID)
+				fmt.Fprintf(os.Stderr, "Debug: lock is stale (PID %d dead), removing and retrying\n", lockPID)
 				}
-				os.Remove(lockPath)
+				_ = os.Remove(lockPath)
 				// Retry once
 				return tryAutoStartDaemon(socketPath)
 			}
@@ -749,9 +749,9 @@ func tryAutoStartDaemon(socketPath string) bool {
 	}
 
 	// Write our PID to lockfile
-	fmt.Fprintf(lockFile, "%d\n", os.Getpid())
-	lockFile.Close()
-	defer os.Remove(lockPath)
+	_, _ = fmt.Fprintf(lockFile, "%d\n", os.Getpid())
+	_ = lockFile.Close()
+	defer func() { _ = os.Remove(lockPath) }()
 
 	// Under lock: check for stale socket and clean up if necessary
 	if _, err := os.Stat(socketPath); err == nil {
@@ -778,11 +778,11 @@ func tryAutoStartDaemon(socketPath string) bool {
 
 		// Socket is stale (connect failed and PID dead/missing) - safe to remove
 		if os.Getenv("BD_DEBUG") != "" {
-			fmt.Fprintf(os.Stderr, "Debug: socket is stale, cleaning up\n")
+		fmt.Fprintf(os.Stderr, "Debug: socket is stale, cleaning up\n")
 		}
-		os.Remove(socketPath)
+		_ = os.Remove(socketPath)
 		if pidFile != "" {
-			os.Remove(pidFile)
+		_ = os.Remove(pidFile)
 		}
 	}
 
@@ -843,7 +843,7 @@ func tryAutoStartDaemon(socketPath string) bool {
 	}
 
 	// Reap the process to avoid zombies
-	go cmd.Wait()
+	go func() { _ = cmd.Wait() }()
 
 	// Wait for socket to be ready with actual connection test
 	if waitForSocketReadiness(socketPath, 5*time.Second) {
@@ -1483,22 +1483,22 @@ func flushToJSONL() {
 	encoder := json.NewEncoder(f)
 	for _, issue := range issues {
 		if err := encoder.Encode(issue); err != nil {
-			f.Close()
-			os.Remove(tempPath)
+			_ = f.Close()
+			_ = os.Remove(tempPath)
 			recordFailure(fmt.Errorf("failed to encode issue %s: %w", issue.ID, err))
 			return
 		}
 	}
 
 	if err := f.Close(); err != nil {
-		os.Remove(tempPath)
+		_ = os.Remove(tempPath)
 		recordFailure(fmt.Errorf("failed to close temp file: %w", err))
 		return
 	}
 
 	// Atomic rename
 	if err := os.Rename(tempPath, jsonlPath); err != nil {
-		os.Remove(tempPath)
+		_ = os.Remove(tempPath)
 		recordFailure(fmt.Errorf("failed to rename file: %w", err))
 		return
 	}

cmd/bd/merge.go

@@ -294,35 +294,43 @@ func updateMergeTextReferences(ctx context.Context, sourceIDs []string, targetID
 
 			// Update description
 			if issue.Description != "" && re.MatchString(issue.Description) {
-				if _, exists := updates["description"]; !exists {
-					updates["description"] = issue.Description
-				}
-				updates["description"] = re.ReplaceAllString(updates["description"].(string), replacementText)
+			if _, exists := updates["description"]; !exists {
+			updates["description"] = issue.Description
 			}
+			if desc, ok := updates["description"].(string); ok {
+			  updates["description"] = re.ReplaceAllString(desc, replacementText)
+			}
+		}
 
 			// Update notes
 			if issue.Notes != "" && re.MatchString(issue.Notes) {
-				if _, exists := updates["notes"]; !exists {
-					updates["notes"] = issue.Notes
-				}
-				updates["notes"] = re.ReplaceAllString(updates["notes"].(string), replacementText)
+			if _, exists := updates["notes"]; !exists {
+			updates["notes"] = issue.Notes
+			}
+			if notes, ok := updates["notes"].(string); ok {
+			  updates["notes"] = re.ReplaceAllString(notes, replacementText)
+			}
 			}
 
 			// Update design
 			if issue.Design != "" && re.MatchString(issue.Design) {
-				if _, exists := updates["design"]; !exists {
-					updates["design"] = issue.Design
-				}
-				updates["design"] = re.ReplaceAllString(updates["design"].(string), replacementText)
+			if _, exists := updates["design"]; !exists {
+			 updates["design"] = issue.Design
+			 }
+			if design, ok := updates["design"].(string); ok {
+			  updates["design"] = re.ReplaceAllString(design, replacementText)
+			 }
 			}
 
 			// Update acceptance criteria
 			if issue.AcceptanceCriteria != "" && re.MatchString(issue.AcceptanceCriteria) {
-				if _, exists := updates["acceptance_criteria"]; !exists {
-					updates["acceptance_criteria"] = issue.AcceptanceCriteria
-				}
-				updates["acceptance_criteria"] = re.ReplaceAllString(updates["acceptance_criteria"].(string), replacementText)
+			 if _, exists := updates["acceptance_criteria"]; !exists {
+				updates["acceptance_criteria"] = issue.AcceptanceCriteria
 			}
+			if ac, ok := updates["acceptance_criteria"].(string); ok {
+				updates["acceptance_criteria"] = re.ReplaceAllString(ac, replacementText)
+			}
+		}
 		}
 
 		// Apply updates if any

cmd/bd/renumber.go

@@ -294,7 +294,7 @@ func renumberIssuesInDB(ctx context.Context, prefix string, idMapping map[string
 	// After renumbering to bd-1..bd-N, set counter to N so next issue is bd-(N+1)
 	// We need to FORCE set it (not MAX) because counter may be higher from deleted issues
 	// Strategy: Reset (delete) the counter row, then SyncAllCounters recreates it from actual max ID
-	sqliteStore := store.(*sqlite.SQLiteStorage)
+	sqliteStore, _ := store.(*sqlite.SQLiteStorage)
 	if err := sqliteStore.ResetCounter(ctx, prefix); err != nil {
 		return fmt.Errorf("failed to reset counter: %w", err)
 	}

cmd/bd/repos.go

@@ -18,7 +18,7 @@ var reposCmd = &cobra.Command{
 This command requires a running global daemon (bd daemon --global).
 It allows you to view and aggregate work across all cached repositories.`,
 	Run: func(cmd *cobra.Command, args []string) {
-		cmd.Help()
+		_ = cmd.Help()
 	},
 }
 

cmd/bd/sync.go

@@ -312,8 +312,8 @@ func exportToJSONL(ctx context.Context, jsonlPath string) error {
 	}
 	tempPath := tempFile.Name()
 	defer func() {
-		tempFile.Close()
-		os.Remove(tempPath)
+		_ = tempFile.Close()
+		_ = os.Remove(tempPath)
 	}()
 
 	// Write JSONL