fix: use merged flags in archive cmd and move defer after error checks

- Fix archive cmd passing only archive-specific Flags instead of the
  merged flags variable that includes browser flags (#8)
- Move defer DeferClose() after error checks in 6 locations to prevent
  calling Close on nil values (#19):
  - sites/duckduckgo/cmd/duckduckgo/main.go
  - sites/duckduckgo/duckduckgo.go
  - sites/google/cmd/google/main.go
  - sites/wegmans/cmd/wegmans/main.go
  - sites/wegmans/wegmans.go
  - sites/aislegopher/aislegopher.go

Closes #8, #19

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

sites/wegmans/cmd/wegmans/main.go

@@ -38,11 +38,10 @@ func main() {
 			cfg := Flags.ToConfig(cmd)
 
 			b, err := browser.FromCommand(ctx, cmd)
-			defer extractor.DeferClose(b)
-
 			if err != nil {
 				return fmt.Errorf("error creating browser: %w", err)
 			}
+			defer extractor.DeferClose(b)
 			arg := cmd.Args().First()
 
 			if arg == "" {