[DO NOT MERGE] Email notification system (#4338)

* Migration

* Fixup db models

* Redis

* Stuff

* Switch PKs to BIGSERIALs, insert to notifications_deliveries when inserting notifications

* Queue, templates

* Query cache

* Fixes, fixtures

* Perf, cache template data & HTML bodies

* Notification type configuration, ResetPassword notification type

* Reset password

* Query cache

* Clippy + fmt

* Traces, fix typo, fix user email in ResetPassword

* send_email

* Models, db

* Remove dead code, adjust notification settings in migration

* Clippy fmt

* Delete dead code, fixes

* Fmt

* Update apps/labrinth/src/queue/email.rs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Remove old fixtures

* Unify email retry delay

* Fix type

* External notifications

* Remove `notifications_types_preference_restrictions`, as user notification preferences is out of scope for this PR

* Query cache, fmt, clippy

* Fix join in get_many_user_exposed_on_site

* Remove migration comment

* Query cache

* Update html body urls

* Remove comment

* Add paymentfailed.service variable to PaymentFailed notification variant

* Fix compile error

* Fix deleting notifications

* Update apps/labrinth/src/database/models/user_item.rs

Co-authored-by: Josiah Glosson <soujournme@gmail.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Update apps/labrinth/src/database/models/user_item.rs

Co-authored-by: Josiah Glosson <soujournme@gmail.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Update Cargo.toml

Co-authored-by: Josiah Glosson <soujournme@gmail.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Update apps/labrinth/migrations/20250902133943_notification-extension.sql

Co-authored-by: Josiah Glosson <soujournme@gmail.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Address review comments

* Fix compliation

* Update apps/labrinth/src/database/models/users_notifications_preferences_item.rs

Co-authored-by: Josiah Glosson <soujournme@gmail.com>
Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>

* Use strfmt to format emails

* Configurable Reply-To

* Configurable Reply-To

* Refactor for email background task

* Send some emails inline

* Fix account creation email check

* Revert "Use strfmt to format emails"

This reverts commit e0d6614afe51fa6349918377e953ba294c34ae0b.

* Reintroduce fill_template

* Set password reset email inline

* Process more emails per index

* clippy fmt

* Query cache

---------

Signed-off-by: François-Xavier Talbot <108630700+fetchfern@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Josiah Glosson <soujournme@gmail.com>

Cargo.lock

@@ -4442,11 +4442,13 @@ version = "0.11.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5cb54db6ff7a89efac87dba5baeac57bb9ccd726b49a9b6f21fb92b3966aaf56"
 dependencies = [
+ "async-trait",
  "base64 0.22.1",
  "chumsky",
  "email-encoding",
  "email_address",
  "fastrand 2.3.0",
+ "futures-io",
  "futures-util",
  "hostname",
  "httpdate",
@@ -4459,6 +4461,7 @@ dependencies = [
  "rustls-native-certs 0.8.1",
  "socket2 0.6.0",
  "tokio",
+ "tokio-rustls 0.26.2",
  "url",
 ]