feat: add transfer service adapters

README.md

@@ -19,9 +19,12 @@ derives canonical resource identities and selection ranges, builds lazy content
 trees, and reports only safe Syncthing folders below the configured root.
 Renamed/noncanonical torrent paths remain visible but are marked noncanonical
 so later job preflight can reject them without hiding the resource.
-The qBittorrent read adapter uses cookie authentication, bounded responses,
-one reauthentication attempt on session expiry, hash-scoped file/metainfo
-fetches, and never logs credentials, cookies, response bodies, or endpoints.
+The qBittorrent adapter uses cookie authentication, bounded responses, one
+reauthentication attempt on session expiry, and hash-scoped file/metainfo
+fetches. Its mutation boundary adds targets stopped, applies only selected vs
+skipped state, supports qBittorrent 4 pause and qBittorrent 5 stop semantics,
+performs guarded full rechecks, and removes entries without requesting data
+deletion. It never logs credentials, cookies, response bodies, or endpoints.
 Durable inventory commands now stream bounded atomic summary, lookup, and
 content-tree chunks. Page tokens are guarded by timestamp-independent snapshot
 revisions, stale trees fail explicitly, and slow scans run outside the socket
@@ -39,6 +42,9 @@ then sparse-aware copy fallback; every intent/result is journaled in SQLite.
 Receiver materialization never overwrites a path, can reuse a same-size regular
 file for later qBittorrent verification, and replays completed operations
 idempotently after a database reopen.
+The Syncthing transfer observer requests scoped rescans and combines verified
+local manifest payloads, folder completion, and outstanding job-prefix needs;
+an advisory percentage alone is never treated as transfer completion.
 
 ```bash
 archive-client --config /etc/archive-control/client.toml --check-config