refactor: session scoped metro graph [WPB-25946]

[Garzas]

https://wearezeta.atlassian.net/browse/WPB-25946

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PR Submission Checklist for internal contributors

• The PR Title

  • conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
  • contains a reference JIRA issue number like SQPIT-764
  • answers the question: If merged, this PR will: ... ³

• The PR Description

  • is free of optional paragraphs and you have filled the relevant parts to the best of your ability

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What's new in this PR?

This PR makes Metro-created ViewModels session-aware and removes the old Hilt wireViewModel helper surface.

Main changes:

• adds viewModelScopeKey to MetroViewModelGraph
• scopes Metro ViewModel keys by the current user id
• exposes current valid user id from WireActivityViewModel
• recreates WireActivity graph-backed ViewModels with a user-scoped key
• migrates remaining wireViewModel call sites in navigation, Home, Import Media, and App Lock to Metro/Hilt bridge helpers
• removes AssistedViewModelExt.kt
• removes the Hilt/Resaca scoped ViewModel fallback from ViewModelScoped.kt

Why?

The temporary Hilt bridge can otherwise keep a ViewModel/factory graph tied to the previous @CurrentAccount after account switch.

This PR does not remove the bridge yet, but it makes the current bridge session-aware and removes the old generic Hilt ViewModel helper so the final cleanup can focus on replacing the bridge with an explicit SessionGraph(userId).

[pull-request-size]

Ups 🫰🟨

This PR is too big. Please try to break it up into smaller PRs.

[codecov]

Codecov Report

❌ Patch coverage is 39.28571% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 49.59%. Comparing base (1240234) to head (7d0b7fd).

Files with missing lines	Patch %	Lines
...rc/main/kotlin/com/wire/android/ui/WireActivity.kt	0.00%	13 Missing ⚠️
...otlin/com/wire/android/ui/WireActivityViewModel.kt	73.33%	0 Missing and 4 partials ⚠️

❌ Your patch check has failed because the patch coverage (39.28%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4916      +/-   ##
===========================================
- Coverage    49.63%   49.59%   -0.05%     
===========================================
  Files          630      642      +12     
  Lines        22530    22565      +35     
  Branches      3427     3429       +2     
===========================================
+ Hits         11182    11190       +8     
- Misses       10311    10337      +26     
- Partials      1037     1038       +1     

Files with missing lines	Coverage Δ
.../ui/authentication/AuthenticationViewModelGraph.kt	0.00% <ø> (ø)
...lin/com/wire/android/ui/home/HomeViewModelGraph.kt	0.00% <ø> (ø)
...re/android/feature/cells/ui/CellsViewModelGraph.kt	0.00% <ø> (ø)
...otlin/com/wire/android/ui/WireActivityViewModel.kt	75.50% <73.33%> (+0.31%)	⬆️
...rc/main/kotlin/com/wire/android/ui/WireActivity.kt	0.00% <0.00%> (ø)

... and 10 files with indirect coverage changes

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[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud