fix: show users in email multiselect

[ps173]

EmailMultiSelect destructured allUsers straight from the users store. Pinia unwraps the computed to a plain array on destructuring, so allUsers.value was undefined and the users list was always empty. That affected the Add Existing User modal. This uses storeToRefs so the list stays reactive and updates once the full user fetch lands.

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[mergify]

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[greptile-apps]

Confidence Score: 5/5

[Medium impact] This change appears safe to merge.

_{Reviews (1) · Last reviewed commit: "fix: show users in email multiselect" · Reviewed by Greptile}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.73%. Comparing base (9f214ef) to head (579d45c).
⚠️ Report is 10 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3072      +/-   ##
===========================================
+ Coverage    76.56%   76.73%   +0.17%     
===========================================
  Files          190      194       +4     
  Lines        14916    15081     +165     
===========================================
+ Hits         11421    11573     +152     
- Misses        3495     3508      +13     

see 6 files with indirect coverage changes

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