Backport of [ui] When a purged/404-ing job is detected, boot the user out of that job and back to the index into release/1.6.x

[hc-github-team-nomad-core]

Backport

This PR is auto-generated from #17915 to be assessed for backporting due to the inclusion of the label backport/1.6.x.

The below text is copied from the body of the original PR.

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• In the event that a job is removed/purged/GC'd from elsewhere while the user is actively on a job page, this PR causes an event to fire that 1. boots the user back to the jobs index page, and 2. gives them a sticky notification about what happened.
• Moves the "job watcher" from jobs.job.index level to jobs.job level, so a "yoinked" job can be observed from anyplace within the job's subnav, not just the index page
• extends the watchRecord watcher util to accept a shouldSurfaceErrors param. This is experimental, but makes it so that elsewhere we can check this.model.watchers.{}.isError, where before it was being yielded but not set on the watcher itself.

Resolves #17757

[github-actions]

Ember Test Audit comparison

	release/1.6.x	01ce5ef	change
passes	1496	1498	+2
failures	1	1	0
flaky	0	0	0
duration	000ms	000ms	-000ms