Add support for modules

content/client-server-api/modules/server_notices.md

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+---
+type: module
+weight: 320
+---
+
+### Server Notices
+
+Homeserver hosts often want to send messages to users in an official
+capacity, or have resource limits which affect a user's ability to use
+the homeserver. For example, the homeserver may be limited to a certain
+number of active users per month and has exceeded that limit. To
+communicate this failure to users, the homeserver would use the Server
+Notices room.
+
+The aesthetics of the room (name, topic, avatar, etc) are left as an
+implementation detail. It is recommended that the homeserver decorate
+the room such that it looks like an official room to users.
+
+#### Events
+
+Notices are sent to the client as normal `m.room.message` events with a
+`msgtype` of `m.server_notice` in the server notices room. Events with a
+`m.server_notice` `msgtype` outside of the server notice room must be
+ignored by clients.
+
+The specified values for `server_notice_type` are:
+
+`m.server_notice.usage_limit_reached`  
+The server has exceeded some limit which requires the server
+administrator to intervene. The `limit_type` describes the kind of limit
+reached. The specified values for `limit_type` are:
+
+`monthly_active_user`  
+The server's number of active users in the last 30 days has exceeded the
+maximum. New connections are being refused by the server. What defines
+"active" is left as an implementation detail, however servers are
+encouraged to treat syncing users as "active".
+
+{{m\_room\_message\_m\_server\_notice\_event}}
+
+#### Client behaviour
+
+Clients can identify the server notices room by the `m.server_notice`
+tag on the room. Active notices are represented by the [pinned
+events](#m-room-pinned-events) in the server notices room. Server notice
+events pinned in that room should be shown to the user through special
+UI and not through the normal pinned events interface in the client. For
+example, clients may show warning banners or bring up dialogs to get the
+user's attention. Events which are not server notice events and are
+pinned in the server notices room should be shown just like any other
+pinned event in a room.
+
+The client must not expect to be able to reject an invite to join the
+server notices room. Attempting to reject the invite must result in a
+`M_CANNOT_LEAVE_SERVER_NOTICE_ROOM` error. Servers should not prevent
+the user leaving the room after joining the server notices room, however
+the same error code must be used if the server will prevent leaving the
+room.
+
+#### Server behaviour
+
+Servers should manage exactly 1 server notices room per user. Servers
+must identify this room to clients with the `m.server_notice` tag.
+Servers should invite the target user rather than automatically join
+them to the server notice room.
+
+How servers send notices to clients, and which user they use to send the
+events, is left as an implementation detail for the server.