[PM-39767] fix: Show upgrade pending alert when upgrading via Settings > Plan

[KatherineInCode]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-39767

📔 Objective

Fixes a bug where initiating the Premium upgrade flow via Settings > Plan never showed the "Upgrade Pending" dialog when the post-payment sync call was interrupted — even though the identical scenario worked correctly from the Vault tab's upgrade CTA.

Root cause: the "Upgrade Pending" alert is driven by DefaultPremiumUpgradeHelper, which subscribes to the checkout-status publisher before navigating to the Premium upgrade screen. Vault and Send screens already construct this helper; SettingsProcessor.navigateToPlan() navigated straight to .premiumUpgrade without ever creating it, so nothing was ever subscribed to catch the .pending status on that path.

Fix: wire SettingsProcessor into the same helper the other 8 entry points already use — SettingsRoute now conforms to PremiumUpgradeRoute, gaining an associated DismissAction on its .dismiss case (mirroring VaultRoute), and navigateToPlan() routes through premiumUpgradeHelper.startInAppPremiumUpgrade() instead of navigating directly.

Giving .dismiss an associated value surfaced a few unrelated pre-existing call sites that referenced it bare (no parens) in ExportVaultProcessor, PendingRequestsProcessor, and DeleteAccountProcessor — fixed those to the explicit .dismiss() call form, since a defaulted associated value isn't auto-applied outside of a direct call expression.

This is a narrower fix than a fuller centralization (moving pending-checkout detection into a shared app-lifetime service) that was evaluated and intentionally shelved as out of scope for this ticket — worth a follow-up ticket if we want to prevent a future entry point from repeating this same gap.

📸 Screenshots

Not applicable — no UI changes.

[codecov]

Codecov Report

❌ Patch coverage is 72.72727% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.27%. Comparing base (438d632) to head (4ed1444).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...Platform/Settings/Settings/SettingsProcessor.swift	37.50%	5 Missing ⚠️
...red/UI/Platform/Settings/SettingsCoordinator.swift	90.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2873      +/-   ##
==========================================
- Coverage   81.27%   81.27%   -0.01%     
==========================================
  Files        1028     1028              
  Lines       66164    66177      +13     
==========================================
+ Hits        53773    53783      +10     
- Misses      12391    12394       +3     

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