👌 [RUM-10290] Remove built extensions from ignored in eslint.config

[BeltranBulbarellaDD]

… ignored in eslint.config.mjs

Motivation

Currently we ignore the browser extensions we use for testing form eslint rules. The aim of this PR is to remove that rule.

Changes

Added a ts.config file to base-extension. Migrated files to be in typescript.
Fixed linter errors in base-extension

Test instructions

Should build, pass CI and most importantly be able to release.

Checklist

• Tested locally
• Tested on staging
• Added unit tests for this change.
• Added e2e/integration tests for this change.

[cit-pr-commenter]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	146.84 KiB	146.84 KiB	0 B	0.00%	✅
Rum Recorder	18.02 KiB	18.02 KiB	0 B	0.00%	✅
Rum Profiler	4.63 KiB	4.63 KiB	0 B	0.00%	✅
Logs	51.72 KiB	51.72 KiB	0 B	0.00%	✅
Flagging	0 B	935 B	935 B	N/A%	✅
Rum Slim	106.46 KiB	106.46 KiB	0 B	0.00%	✅
Worker	23.59 KiB	23.59 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base Average Cpu Time (ms)	Local Average Cpu Time (ms)	𝚫
addglobalcontext	0.007	0.007	-0.000
addaction	0.027	0.022	-0.005
addtiming	0.005	0.005	-0.000
adderror	0.025	0.020	-0.005
startstopsessionreplayrecording	0.001	0.001	-0.000
startview	0.005	0.005	-0.000
logmessage	0.025	0.022	-0.003

🧠 Memory Performance

Action Name	Base Consumption Memory (bytes)	Local Consumption Memory (bytes)	𝚫 (bytes)
addglobalcontext	25.06 KiB	25.69 KiB	650 B
addaction	52.27 KiB	56.08 KiB	3.80 KiB
addtiming	24.97 KiB	26.25 KiB	1.28 KiB
adderror	56.36 KiB	57.25 KiB	914 B
startstopsessionreplayrecording	25.34 KiB	24.74 KiB	-618 B
startview	429.73 KiB	430.36 KiB	651 B
logmessage	56.07 KiB	57.36 KiB	1.29 KiB

🔗 RealWorld

[BeltranBulbarellaDD]

/to-staging

[dd-devflow]

View all feedbacks in Devflow UI.

2025-06-10 07:19:45 UTC ℹ️ Start processing command /to-staging

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2025-06-10 07:19:53 UTC ℹ️ Branch Integration: starting soon, merge expected in approximately 0s (p90)

Commit d2b430ed94 will soon be integrated into staging-24.

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2025-06-10 07:35:40 UTC ℹ️ Branch Integration: This commit was successfully integrated

Commit d2b430ed94 has been merged into staging-24 in merge commit 15d1aff633.

Check out the triggered pipeline on Gitlab 🦊

If you need to revert this integration, you can use the following command: /code revert-integration -b staging-24