chore: improve DX scripts, fix test suite, and harden tooling

Scripts:
- remote.sh: remove unused open_browser() function
- deploy-remote.sh: add DB backup before deploy, --skip-backup flag, step numbering
- db-backup.sh: fix macOS compat (xargs -r is GNU-only), use portable approach
- db-restore.sh: add safety backup before restore, SQL file validation, file size display
- logs.sh: default to no-follow with --tail=100, order-independent arg parsing
- docker-cleanup.sh: add Docker health check, colored output
- test-sequential.sh: exclude *.integration.test.ts by default, add --integration flag
- simulate-ci.sh: pass --integration flag (has real DB)

Tests:
- db.test.ts: fix mock path from ./DrizzleClient to @shared/db/DrizzleClient
- server.settings.test.ts: rewrite mocks for gameSettingsService (old config/saveConfig removed)
- server.test.ts: add missing config.lootdrop and BotClient mocks, complete DrizzleClient chain
- indexes.test.ts: rename to indexes.integration.test.ts (requires live DB)

Config:
- package.json: test script uses sequential runner, add test:ci and db:restore aliases
- deploy.yml: use --integration flag in CI (has Postgres service)

shared/scripts/db-backup.sh

@@ -2,6 +2,10 @@
 # =============================================================================
 # Aurora Database Backup Script
 # =============================================================================
+# Creates a timestamped PostgreSQL backup and retains the last 10 backups.
+#
+# Usage: ./db-backup.sh
+# =============================================================================
 
 set -e
 
@@ -37,9 +41,13 @@ if docker ps | grep -q aurora_db; then
        echo -e "  📂 File: $BACKUP_FILE"
        echo -e "  📏 Size: $(du -h "$BACKUP_FILE" | cut -f1)"
        
-       # Keep only last 10 backups
+       # Keep only last 10 backups (cross-platform: works on macOS and Linux)
        cd "$BACKUP_DIR"
-       ls -t backup_*.sql | tail -n +11 | xargs -r rm --
+       OLD_BACKUPS=$(ls -t backup_*.sql 2>/dev/null | tail -n +11)
+       if [ -n "$OLD_BACKUPS" ]; then
+         echo "$OLD_BACKUPS" | xargs rm --
+         echo -e "  ${GREEN}✓${NC} Pruned old backups"
+       fi
      else
        echo -e "  ${RED}✗${NC} Backup created but empty. Something went wrong."
        rm -f "$BACKUP_FILE"