feat: Remove 'Improved signature requests' setting toggle

[pedronfigueiredo]

Description

Removes the settings toggle for redesigned signatures. Removes e2e tests used for old flows no longer supported. For test/e2e/tests/metrics/signature-approved.spec.js, the tests were migrated to the redesigned confirmation screen.

Related issues

Fixes: https://github.com/MetaMask/MetaMask-planning/issues/3029

Manual testing steps

1. Go to this page...

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

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.

[metamaskbot]

Builds ready [07ae676]

• builds: chrome, firefox
• builds (flask): chrome, firefox
• builds (MMI): chrome
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6, 7
  • common: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13
  • ui: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13
  • content-script: 0
  • offscreen: 0

Page Load Metrics (1581 ± 71 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	450	2023	1516	281	135
		domContentLoaded	1396	1999	1566	146	70
		load	1409	2027	1581	147	71
		domInteractive	25	97	39	16	8
		backgroundConnect	6	59	12	11	5
		firstReactRender	15	69	35	23	11
		getState	4	42	10	11	5
		initialActions	0	1	0	0	0
		loadScripts	1001	1540	1161	128	62
		setupStore	5	52	12	14	7
		uiStartup	1575	2355	1809	196	94

Bundle size diffs [🚀 Bundle size reduced!]

• background: 445 Bytes (0.01%)
• ui: -561 Bytes (-0.01%)
• common: -483 Bytes (-0.01%)

[metamaskbot]

Builds ready [8302d8c]

• builds: chrome, firefox
• builds (flask): chrome, firefox
• builds (MMI): chrome
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6, 7
  • common: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13
  • ui: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13
  • content-script: 0
  • offscreen: 0

Page Load Metrics (1760 ± 60 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1548	1959	1764	125	60
		domContentLoaded	1536	1900	1721	118	56
		load	1550	1968	1760	126	60
		domInteractive	22	138	44	28	13
		backgroundConnect	7	92	38	27	13
		firstReactRender	16	99	42	27	13
		getState	5	64	13	14	7
		initialActions	0	1	0	0	0
		loadScripts	1089	1436	1280	105	50
		setupStore	6	78	19	21	10
		uiStartup	1843	2769	2154	258	124

Bundle size diffs [🚀 Bundle size reduced!]

• background: 445 Bytes (0.01%)
• ui: -1023 Bytes (-0.01%)
• common: -483 Bytes (-0.01%)

[matthewwalsh0]

As mentioned on the other PR, can we just delete the full optional chain as it will no-op if undefined?