fix: Remove 'local' keyword from script-level variable declaration

CRITICAL BUG - Variable Scope
Script uses 'set -e' which causes exit on ANY error. The 'local' keyword
only works inside functions, not at script level. This would cause the
batch analyzer to fail immediately.

Fix:
  - Removed 'local' from all_domains_string declaration (line 97)
  - Variable now correctly declared at script level
  - Script can now run without exiting on scope error

Testing:
  ✓ Bash syntax validation passes
  ✓ All domain collection logic works
  ✓ Traffic percentage calculation correct
  ✓ Fair share allocation correct
  ✓ Edge cases handled (single domain, many domains, no logs)

modules/performance/php-fpm-batch-analyzer.sh

@@ -93,8 +93,7 @@ users=$(list_all_users)
 
 # CRITICAL FIX: Build list of ALL domains on server FIRST
 # This is needed for accurate traffic percentage calculation
-declare -a all_server_domains
-local all_domains_string=""
+all_domains_string=""  # Note: NOT local (function scope only), this is script-level
 while IFS= read -r username; do
     [ -z "$username" ] && continue
     user_domains=$(get_user_domains "$username")