fix: introducing laziness in Transaction Group Details data collection

[ericleponner]

Description:

Changes below:

• move some logic from TransactionGroupDetails to new TransactionGroupRow and SignGroupItemButton to divide complexity
• introduce some laziness when computing Sign button state : computation starts only when row becomes visible
• optimize Sign All state computation (it checks that at least one group item is signable ; that's enough)
• temporarily disable calls to GET /transactions/approve/<transactionId> until Approval feature is fully backed

With those changes:

• Sign button flickering is fully removed
• Sign All button flickering is substantially reduced (but still visible when notification arrives and triggers a full page refresh)

Related issue(s):

Fixes #2410

Notes for reviewer:

M   front-end/src/renderer/pages/TransactionGroupDetails/TransactionGroupDetails.vue
    # Now delegates display and update of a row to TransactionGroupRow view.
    # Call to getUserShouldApprove() in fetchGroups() is temporarily disabled
    # to avoid unneeded call to backend (Approve feature is not backed yet).

A   front-end/src/renderer/pages/TransactionGroupDetails/TransactionGroupRow.vue
    # TransactionGroupRow now handles transaction group item display and update.
    # It uses useRevealed() composable to  start state computation only
    # when the row becomes visible in viewport.
    # It also delegate signing status computation to isSignableTransaction().

A   front-end/src/renderer/pages/TransactionGroupDetails/SignGroupItemButton.vue
    # Handle Sign action. Makes sure to emit('transactionSigned') once
    # transaction is signed *and* new transaction data have been retrieved from server.
    # This prevents Sign button to flicker.

M   front-end/src/renderer/utils/transactionSignatureModels/index.ts
    # Added isSignableTransaction() and used it from TransactionGroupRow and TransactionGroupDetails

A   front-end/src/renderer/composables/useRevealed.ts
    # New composable which monitors an html element and invokes a callback
    # when this element becomes visible in the viewport

Checklist

• Documented (Code comments, README, etc.)
• Tested (unit, integration, etc.)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.94%. Comparing base (4087338) to head (85d168d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2430   +/-   ##
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  Coverage   99.94%   99.94%           
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  Files         180      180           
  Lines        7017     7017           
  Branches     1420     1416    -4     
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  Hits         7013     7013           
  Misses          4        4           

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[Copilot]

Pull request overview

This PR refactors the Transaction Group Details page to reduce UI lag/flicker by moving row-level signing logic into dedicated components and deferring expensive “can sign?” computation until rows are visible.

Changes:

• Introduces TransactionGroupRow and SignGroupItemButton to split responsibilities from TransactionGroupDetails.
• Adds useRevealed() composable to lazily start per-row signing-state computation when a row enters the viewport.
• Changes “Sign All” enablement logic to depend on whether at least one signable item exists, instead of tracking signability for every item.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 8 comments.

File	Description
front-end/src/renderer/pages/TransactionGroupDetails/TransactionGroupDetails.vue	Delegates row rendering, adds “first signable item” tracking for Sign All, and updates state after a row signs.
front-end/src/renderer/pages/TransactionGroupDetails/TransactionGroupRow.vue	New row component that lazily computes canSign when revealed and emits row events upward.
front-end/src/renderer/pages/TransactionGroupDetails/SignGroupItemButton.vue	New sign button component that signs a transaction and re-fetches updated transaction data.
front-end/src/renderer/composables/useRevealed.ts	New composable wrapping an IntersectionObserver to trigger callbacks when an element becomes visible.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 8 comments.

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[jbair06]

LGTM - manual testing shows a huge improvement in responsiveness - near instant.