JS downgrades + make `changes` a required job---------Co-authored-by: Bruno Quaresma <bruno@coder.com>Co-authored-by: ケイラ <mckayla@hey.com>Co-authored-by: Ethan <39577870+ethanndickson@users.noreply.github.com>

Relates tocoder/dogfood#189Relates tocoder/internal#1021- Adds new script `scripts/should_deploy.sh` which implements thealgorithm in the linked issue- Changes the `ci.yaml` workflow to run on release branches- Moves the deployment steps out of `ci.yaml` into a new workflow`deploy.yaml` for concurrency limiting purposes- Changes the behavior of image tag pushing slightly:    - Versioned tags will no longer have a `main-` prefix    - `main` branch will still push the `main` and `latest` tags    - `release/x.y` branches will now push `release-x.y` tags- The deploy job will exit early if `should_deploy.sh` returns false- The deploy job will now retag whatever image it's about to deploy as`dogfood`(cherry picked from commite5c8c9b)

…20147) (#20153)Truncates the task prompt used in notifications to a maximum of 160characters. The length of 160 characters was chosen arbitrarily.(cherry picked from commitffcb7a1)