feat(roms): add RomM stack (romm + mariadb) over /storage1/Emulation

New per-domain stack centralizing the emulation/ROM library:

- romm (rommapp/romm:4) + dedicated MariaDB; RomM bundles its own Redis

- library mounts existing EmuDeck tree /storage1/Emulation (RomM Structure A) read-write; tiered binds (config->/config, blobs->/storage1/labdata)

- env_file-only config (no ${VAR}) so the git stack needs no Portainer UI env vars

- Hasheous metadata enabled; IGDB/SteamGridDB/ScreenScraper scaffolded empty

- Caddy: roms.ginnoir.com internal_only -> romm:8080; regenerated bookmarks

bookmarks-domains.html

@@ -51,6 +51,11 @@
             <DT><A HREF="https://stash.ginnoir.com">stash</A>
         </DL><p>
 
+        <DT><H3>GAMES / ROMS (internal)</H3>
+        <DL><p>
+            <DT><A HREF="https://roms.ginnoir.com">roms</A>
+        </DL><p>
+
         <DT><H3>NOTIFICATIONS &amp; RSS (public)</H3>
         <DL><p>
             <DT><A HREF="https://ntfy.ginnoir.com">ntfy</A>