Carve a new nezha:inventory:{read,delete,*} resource family out of
nezha:server:*. Listing and deleting servers/server-groups (GET /server,
/server-group, /ws/server, batch-delete/server[-group], MCP server.list)
now require nezha:inventory:*, while nezha:server:* covers per-server
runtime operations (get, exec, fs, config, metrics, batch-move,
force-update).
Also declare MCP tool OutputSchema for exec/fs/meta/server/transfer and
wrap server.list output in {servers,count} so strict MCP clients accept
the structured result. Correct the /file all-of scope entry and the stale
server:read documentation.