refactor(hachidori): drop the Docker management upload for character dictionaries

Every supported host now takes dictionary ZIPs over the link, so remove
the port 8780 upload, its hachidori.externalHostManagementUrl override and
the hachidori config section. A linked host without linked-import-v1 now
reports the update or manual-import fix.

docs-site/usage.md

@@ -49,9 +49,7 @@ Setup checks the connection and the host's dictionaries before **Finish** unlock
 
 While linked, dictionaries and dictionary settings come from the host. Anki templates, pronunciation sources, custom buttons, and SubMiner's audio and image processing stay local. Frequency annotations use ranks returned with dictionary entries, and SubMiner asks the host for missing ones. Words with no matching definition entry may stay unranked even if a frequency dictionary lists them.
 
-SubMiner sends [character dictionaries](/character-dictionary) to the linked host over the link and replaces the previous one once the import succeeds, retrying while the host is busy. This needs Hachidori 0.2.3 or later on the host. With an older host, sync reports where the merged ZIP is so you can import it from that host's Hachidori settings.
-
-Docker hosts take the upload on their management port (8780) instead. If the host uses a different `ADMIN_PORT` or sits behind a reverse proxy, set `hachidori.externalHostManagementUrl` to its management origin, for example `"http://pve-main:9000"`. This is not the WebSocket sharing address. Browser hosts and local Hachidori do not need this setting.
+SubMiner sends [character dictionaries](/character-dictionary) to the linked host over the link and replaces the previous one once the import succeeds, retrying while the host is busy. The host needs Hachidori 0.2.3 or later, or a current Docker host. With an older host, sync reports where the merged ZIP is so you can import it from that host's Hachidori settings.
 
 ## Picking files