✨ [RUM-6563] Attribute ressource URL to LCP

[RomanGaignault]

Motivation

LCP is often caused by a big image being rendered. If we can find which image was loaded at that time, we could have a field like: @view.largest_contentful_paint_resource_url:https://...

Changes

Adding new field to indicate the ressource url of the largest contentful paint

Testing

• Local
• Staging
• Unit
• End to end

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I have gone over the contributing documentation.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.68%. Comparing base (07a99fa) to head (3749d34).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3154      +/-   ##
==========================================
- Coverage   93.71%   93.68%   -0.03%     
==========================================
  Files         291      291              
  Lines        7670     7670              
  Branches     1747     1747              
==========================================
- Hits         7188     7186       -2     
- Misses        482      484       +2     

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[cit-pr-commenter]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	146.36 KiB	146.40 KiB	45 B	+0.03%	✅
Logs	51.06 KiB	51.06 KiB	0 B	0.00%	✅
Rum Slim	105.14 KiB	105.19 KiB	45 B	+0.04%	✅
Worker	24.50 KiB	24.50 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base Average Cpu Time (ms)	Local Average Cpu Time (ms)	𝚫
addglobalcontext	0.002	0.002	-0.000
addaction	0.036	0.035	-0.001
addtiming	0.001	0.001	-0.000
adderror	0.053	0.048	-0.005
startstopsessionreplayrecording	0.006	0.009	0.004
startview	0.390	0.373	-0.017
logmessage	0.023	0.020	-0.004

🧠 Memory Performance

Action Name	Base Consumption Memory (bytes)	Local Consumption Memory (bytes)	𝚫 (bytes)
addglobalcontext	27.15 KiB	28.42 KiB	1.27 KiB
addaction	56.98 KiB	57.98 KiB	1024 B
addtiming	26.16 KiB	26.94 KiB	800 B
adderror	58.91 KiB	59.40 KiB	497 B
startstopsessionreplayrecording	25.45 KiB	24.82 KiB	-642 B
startview	414.52 KiB	418.08 KiB	3.56 KiB
logmessage	60.40 KiB	60.29 KiB	-113 B

🔗 RealWorld

[sethfowler-datadog]

Before making these changes, you'll want to add the new field to rum-events-format; it goes here.

[sethfowler-datadog]

LGTM!