Fix custom headers in result pages

[matthewwalsh0]

Description

Fixes support for the header property when using the standardised result pages by calling ApprovalController.success or ApprovalController.error.

Also removes the SiteOrigin component from the ConfirmationPage component as an incorrect condition meant it has not been used for the last 6 months and so reintroducing it without validation may cause undesirable visual changes.

Manual Testing Steps

Not currently in use, fixing for adoption in progress.

Screenshots

Pre-merge Author Checklist

• I’ve followed MetaMask Coding Standards.
• I've clearly explained:
  • What problem this PR is solving.
  • How this problem was solved.
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• I’ve indicated what issue this PR is linked to: Fixes #???
• I’ve included tests if applicable.
• I’ve documented any added code.
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  • In case it's not yet "ready for review", I've set it to "draft".
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Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[codecov]

Codecov Report

All modified lines are covered by tests ✅

Comparison is base (89c40cb) 68.38% compared to head (e29b1ac) 68.38%.
Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop   #21076   +/-   ##
========================================
  Coverage    68.38%   68.38%           
========================================
  Files         1008     1008           
  Lines        40288    40284    -4     
  Branches     10779    10773    -6     
========================================
- Hits         27548    27546    -2     
+ Misses       12740    12738    -2     

Files	Coverage Δ
ui/pages/confirmation/confirmation.js	63.57% <ø> (-0.32%)	⬇️
ui/pages/confirmation/templates/error.js	75.00% <ø> (-5.00%)	⬇️
ui/pages/confirmation/templates/success.js	75.00% <ø> (-5.00%)	⬇️
ui/pages/confirmation/util.ts	80.49% <100.00%> (+3.56%)	⬆️

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[metamaskbot]

Builds ready [e29b1ac]

• builds: chrome, firefox
• builds (beta): chrome
• builds (flask): chrome, firefox
• builds (MMI): chrome, firefox
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Background Module Init Stats
• mv3: UI Init Stats
• mv3: Module Load Stats
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• code coverage: Report
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4
  • common: 0, 1, 2, 3, 4, 5, 6
  • content-script: 0
  • contentscript: contentscript
  • disable-console: disable-console
  • inpage: inpage
  • policy-load: policy-load
  • sentry-install: sentry-install
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1027 ± 402 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	92	158	109	17	8
		domContentLoaded	74	156	102	22	11
		load	87	2009	1027	838	402
		domInteractive	74	156	102	22	11

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: -550 Bytes (-0.01%)
• common: 0 Bytes (0.00%)