Increase visibility of outstanding forward ports

[xmo-odoo]

As of this update (2025-01-17) >200 oustanding forward ports (fw or PRs merged more than one week ago)

• oldest one is going on two years
• one team has successfully reached 3 digits

problems

• ~~the metric / display is actually kinda shit, because the forward port can be an hour old but if its PR was merged last week it's outstanding (this is not impossible for complex PRs, or bad weeks with lots of non-deterministic failures, it can take a while for each forward port to be merged and give access to the next one)~~ done, outdating is now based on the creation date of the forward port
• ~~also some forward ports could be counted twice? The sum of all team counters can be more than the outstanding count because outstandings are counted towards both the author and the reviewer, but it doesn't really make sense at the team level...~~ indeed if both author and reviewer are in the same team (e.g. self-review) then the forward ports would be counted twice towards the team's tally, which doesn't make sense
• ~~reminders are on an exponential backoff based on merge date, so no reminders when a blocked fw is finally merged and the next one is created~~ done, reminders are now linear (initially weekly then monthly (actually every 4 weeks)
• what if the reviewiewer changed team (or job)?
• ~~how many people conveniently decide they're bankrupt on github notifications?~~ added email reminders at 6 months
• people don't watch them
  • ~~if logged in (does that happen?) the user should see their own status~~
    • ~~that specific info should be in the default box, and the default view of the page~~
    • if concept of team leads, should also be in the view

possible solutions

• responsibility handoff
  • store team of approver, start slinging?
• more aggressive reminders? (e.g. cap backoff)
• email?
• odoo / discord messages?
• block new PRs?

[xmo-odoo]

Marking as done as most of the items are resolved, the team move / handoff / ... issue should probably be handled in #968 as the reassignment of people is very much involved.