cherry-pick: chore: Use network-specific smart transaction feature flags (#30094)

[dan437]

Description

Cherry pick of: #30094

Related issues

Fixes:

Manual testing steps

1. Turn off some feature flag which is network-specific for smart transactions (e.g. bsc.smartTransactions.extensionActive = false)
2. See that it's being used over a shared one (smartTransactions.extensionActive)

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.

Description

Related issues

Fixes:

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 [45bc2f3]

• 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 (2093 ± 95 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	249	2327	1466	794	381
		domContentLoaded	1613	2383	2069	201	97
		load	1650	2395	2093	198	95
		domInteractive	23	204	66	46	22
		backgroundConnect	10	68	31	19	9
		firstReactRender	17	111	50	27	13
		getState	6	67	31	22	11
		initialActions	0	1	0	0	0
		loadScripts	1184	1798	1553	174	84
		setupStore	8	63	15	11	5
		uiStartup	1938	3205	2426	275	132