Read modules: mail

[chmmou]

Endpoints: get_mailaccounts, get_mailaccount, get_mailforwards (+ filter variant), get_mailforward, get_mailstandardfilter, get_mailinglists.

• internal/mail/ package (or split per resource — to decide during implementation).
• Mapping tests against testdata/mailaccount/{get_mailaccounts,get_mailaccount}_response_success.xml, testdata/mailforward/{get_mailforwards,get_mailforward}_response_success.xml, testdata/mailfilter/get_mailstandardfilter_response_success.xml, testdata/mailinglist/get_mailinglists_response_success.xml, plus matching _response_failed_* fixtures.
• CLI subcommands: kasapi-cli mail accounts list|get, kasapi-cli mail forwards list|get [--address X], kasapi-cli mail filters list, kasapi-cli mail lists list.

Status (2026-05-03)

• All listed fixtures are present, including get_mailinglists (which was originally noted as "fixture to add"). Singular get_mailaccount/get_mailforward fixtures also added.