Fix new clippy lints

WIP: web/auth: use RFC9500 test keys

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

Rename mpot-web crate to mailpot-web

web: update axum-login (not working)

Update grcov report

Add grcov workflow

Document entire `core` create, add CI, tests

WIP: web: implement search history

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

web: load cookie secret from env var if present

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

wip2