Pick the editor landing tab from the team that owns the instance or device

[cstns]

Closes #8749

The editor routes pick the landing tab (Expert or Overview) inside the route redirect, which runs before the instance or device has been fetched. So the check uses whatever team the session last had, or no team at all in a fresh tab. The Expert flags are opt-out, so no team means "enabled" and you land on Expert. By the time the right team loads, the nav hides the Expert tab but the router is already on /editor/expert and the panel stays open.

The backend already blocks Expert for these teams, so this is only about where the UI lands.

I added a small useEditorLandingTab composable that both editor pages call once the entity and its team are loaded. If you're on Expert and the owning team has it off, it moves you to Overview. If the redirect put you on Overview only because the team wasn't known yet and the owning team has Expert on, it moves you to Expert. Going to /editor/overview on purpose is left alone. Only the team that owns the instance or device counts.

This is really a symptom of the app not having a predictable way of hydrating itself. The route redirect runs before anything has loaded the instance, its team or the feature flags, so it has to guess from whatever is in the store. Loading the entity first and then correcting the route is the local workaround. The proper fix is the "Hydrate-Before-Route" pattern from #6519, tracked in #6520: the router waits for the team context and feature flags to be in the store before any route logic or component setup runs, at which point this composable goes away and the redirect can just read the right team.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.35%. Comparing base (bfaaa30) to head (9267313).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8755   +/-   ##
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  Coverage   78.35%   78.35%           
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  Files         474      474           
  Lines       25639    25639           
  Branches     6827     6827           
=======================================
  Hits        20089    20089           
  Misses       5550     5550           

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[hardillb]

Quick local test looks good.

I'll let @n-lark review it technically