On room join, the room object is created before the server's self-presence arrives.
`_getRoomUser()` thus returns `user=None` for the initial presence, which led to
`super().availableReceived(presence)` not being called, resulting in wrong typing of the
room and the room not really being joined.
- Add sync status tracking with bridge signals (`mam_sync_started`, `mam_sync_completed`,
`mam_sync_error`), `mam_sync_statuses_get` method and helper methods that are called
from `plugin_xep_0045`.
- Update "resume" workflow:
- fix settings of last stanza ID, so it's always set (was not set for our own messages)
- own message now use `onMessage` full workflow instead of just store and signal.
- add `flush_archive_batch` at the end of the process.
- Sync status are sent during resumt
- Modernisation (type hints, use of `get_plugin_data`)
- Join method is completely refactored so a room is now joined immediately, and MAM
synchronisation happens in background.
- Legacy history is not used anymore to simplify code.
- Global simplification of the plugin, not more complicated states handling or message
caching.
This is a huge configuration refactoring.
The configuration system now uses Pydantic settings, with better validation, better
support for environment variables and other goodies.
The main config files now use TOML instead of INI, this allow for better handling of
complex types, notably dict.
Plugins, components and frontends can declare their config settings in a class which will
be imported dynamically.
- workflow is now using the normal messages workflow even for history message: previous
workflow was dedicated to MUC and only adding message to history, resulting in other
plugins being skipped.
- new `get_room_user_jid` helps to retrieve easily the JID currently used in a joined
room.
