✨ [RUM-8780] Make developer extension capable of injecting the browser SDK

[BeltranBulbarellaDD]

Motivation

The idea is to be able to inject the SDK on a page that does not have it. Injecting the local version and CDN version.

Changes

Load the extension dist folder, in chrome://extensions/. And on the SDK side go to developer-extension and yarn dev.
Disable the deployed Developer Extension to not have issues.
Added under Datadog Employee mode, the possibility to inject using CDN the SDK on pages that do not have it.

Test instructions

Screen.Recording.2025-09-26.at.16.37.02.mov

Checklist

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

[datadog-datadog-prod-us1]

✅ Tests

🎉 All green!

❄️ No new flaky tests detected
🧪 All tests passed

🎯 Code Coverage
• Patch Coverage: 100.00%
• Total Coverage: 92.67% (+0.00%)

View detailed report

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 0252280 | Docs | Was this helpful? Give us feedback!}

[BeltranBulbarellaDD]

I can probably remove this, the thing is that I was getting 403 so this was the fallback.
Gonna look for a better way.
(Open to suggestions)

[cit-pr-commenter]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	162.08 KiB	162.08 KiB	0 B	0.00%	✅
Rum Recorder	19.78 KiB	19.78 KiB	0 B	0.00%	✅
Rum Profiler	4.89 KiB	4.89 KiB	0 B	0.00%	✅
Logs	55.77 KiB	55.77 KiB	0 B	0.00%	✅
Flagging	944 B	944 B	0 B	0.00%	✅
Rum Slim	119.06 KiB	119.06 KiB	0 B	0.00%	✅
Worker	23.60 KiB	23.60 KiB	0 B	0.00%	✅

🚀 CPU Performance

Pending...

🧠 Memory Performance

Pending...

🔗 RealWorld