fix dispatcher hyphen bug in 4 more services

setup.sh's run_service() looks up install_<name> using the literal
hyphenated registered name, not an underscore-converted one. borg-backup,
calibre-web, gaming-backup, and stirling-pdf all used underscored function
names and were therefore uninstallable ("has no install_<name>"). Same
fix already applied to ai-gpu/ai-stack; this closes out the rest of the
repo-wide audit.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nb2vJ8W7bHKx1JXVvpCraH

services/borg-backup.sh

@@ -207,7 +207,7 @@ fi
 
 register_service borg-backup backup "Encrypted backup of all Docker services via Borg"
 
-install_borg_backup() {
+install_borg-backup() {
     require_docker || return 1
 
     local DIR="$DOCKER_DIR/borg-backup"
@@ -660,4 +660,4 @@ SVCEOF
 }
 
 # Run immediately when executed directly (deferred until after function definition)
-[[ "${_RUN_STANDALONE:-0}" == 1 ]] && install_borg_backup
+[[ "${_RUN_STANDALONE:-0}" == 1 ]] && install_borg-backup