* implement supplier templating to allow addressbooks and contacts to
come from various sources ("suppliers", thus) as opposed to solely
from JMAP
* add creating, deleting, updating, getting changes
* add some search filter parameters, currently incomplete
* don't run the Stalwart container in recovery mode first, just run it
in "proper" mode, import the configuration and use it like that,
which only requires skipping the "destroy" steps
* add code documentation and logging
* replace the text templating of the Stalwart snapshot by doing the
same as the formatting script was doing, but directly in Go, removing
an additional step to perform when modifying a Stalwart
configuration to use in the integration tests
* refactor APIs in JMAP and Groupware in order to implement pagination
across multiple accountIds and multiple suppliers (currently
implemented using a mock supplier for contacts)
* requires go 1.26 due to use of self-reflecting generics type
constraints
* still missing: query criteria and sorting parameters
* still missing: multi-accountId support for emails
* errors are now all just 'error' in the APIs, instead of the
specialized implementations, and are interpreted dynamically where
necessary in order to transform them into HTTP responses
* remove position, anchor, anchorOffset as individual query parameters
as we now only support a 'next=...' token for subsequent pages
(except in emails for now), and use jmap.QueryParams instead; those
tokens have a header character for the format, followed by a JSON
encoded QueryParams map, all wrapped into base62 to make it clearer
that it is meant to be an opaque token, and not a parameter clients
should tinker with or construct themselves
* introduce QueryParamsSupplier as an interface to provide QueryParams
for various scenarios (single supplier, multiple supplier, ...) per
accountId
* implement multi-supplier template methods slist and squery
* in the JMAP API as well as in several places in the Groupware
framework, use a single jmap.Response[T] object to return the
payload, the language, the session state and the etag/state instead
of individual multi-valued return values
