This is preparatory work for letting some users access admin-exclusive
service commands, such as creating new users.
This adds a boolean admin flag to the User schema. Old users will stay
non-admin after the DB migration.
For Network and Channel, the database only needed to define one Store
operation to create/update a record. However since User is missing an ID
we couldn't have a single StoreUser function like other types. We had
CreateUser and UpdatePassword. As new User fields get added (e.g. the
upcoming Admin flag) this isn't sustainable.
We could have CreateUser and UpdateUser, but this wouldn't be consistent
with other types. Instead, introduce User.Created which indicates
whether the record is already stored in the DB. This can be used in a
new StoreUser function to decide whether we need to UPDATE or INSERT
without relying on SQL constraints and INSERT OR UPDATE.
The ListUsers and GetUser functions set User.Created to true.
Channels can now be detached by leaving them with the reason "detach",
and re-attached by joining them again. Upon detaching the channel is
no longer forwarded to downstream connections. Upon re-attaching the
history buffer is sent.
Store the list of configured channels in the network data structure.
This removes the need for a database lookup and will be useful for
detached channels.
Some servers use custom IRC bots with custom commands for registering to
specific services after connection.
This adds support for setting custom raw IRC messages, that will be
sent after registering to a network.
It also adds support for a custom flag.Value type for string
slice flags (flags taking several string values).
The database is now initialized automatically on first run. The schema
version is stored in SQLite's user_version special field. Migrations are
stored in an array and applied based on the schema version.
We now store SASL credentials in the database and automatically populate
them on NickServ REGISTER/IDENTIFY.
References: https://todo.sr.ht/~emersion/jounce/10
