Fix three crash-looping services: koha-db, homebox, vaultwarden

koha-db: compose used MYSQL_ROOT_PASSWORD/MYSQL_DATABASE/MYSQL_USER/
MYSQL_PASSWORD, but this mariadb:11 image version's entrypoint doesn't
recognize MYSQL_ROOT_PASSWORD as any of its accepted root-password
options at all. Confirmed live: "Database is uninitialized and password
option is not specified" on every start, even though DB_ROOT_PASS was
correctly generated and present in .env the whole time. Switched all
four to their MARIADB_* equivalents.

homebox: a newer homebox release requires HBOX_AUTH_API_KEY_PEPPER (at
least 32 bytes) or the container panics on startup — this installer
never set it. Generate one with generate_password 48 and wire it
through .env + the compose environment block.

vaultwarden: the SMTP setup prompts let you enter a host but leave
"SMTP from address" blank (no default), writing a half-configured state
Vaultwarden refuses to start with ("Both SMTP_HOST and SMTP_FROM need
to be set"). Validate after prompting — if SMTP_HOST is set but
SMTP_FROM came back empty, disable SMTP entirely instead of writing a
config known to crash the container.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H4k6J1qXXyYxhGEgnJaMvn

services/koha.sh

@@ -440,10 +440,16 @@ ${_CADDY_NET_ENTRY}
     hostname: koha-db
     restart: unless-stopped
     environment:
-      MYSQL_ROOT_PASSWORD: \${DB_ROOT_PASS}
-      MYSQL_DATABASE: koha_default
-      MYSQL_USER: koha_default
-      MYSQL_PASSWORD: \${DB_PASS}
+      # MARIADB_* not MYSQL_* — confirmed live, this image version's
+      # entrypoint doesn't recognize MYSQL_ROOT_PASSWORD as any of its
+      # accepted root-password options at all ("Database is uninitialized
+      # and password option is not specified"), so the container crash-
+      # loops even though DB_ROOT_PASS is correctly generated and present
+      # in .env the whole time. Switched all four for consistency.
+      MARIADB_ROOT_PASSWORD: \${DB_ROOT_PASS}
+      MARIADB_DATABASE: koha_default
+      MARIADB_USER: koha_default
+      MARIADB_PASSWORD: \${DB_PASS}
     volumes:
       - ./data:/var/lib/mysql
     networks: