adlrb/another prestart

[mormubis]

• docs: map existing codebase
• feat: implement telemetry split initialization pattern
• feat: add RUM telemetry collection in preStart
• feat: integrate RUM transport in start phase
• test: add comprehensive test suite for telemetry initialization
• chore: clean up planning artifacts

Motivation

Changes

Test instructions

Checklist

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

[github-actions]

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[cit-pr-commenter-54b7da]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	165.78 KiB	165.93 KiB	+149 B	+0.09%	✅
Rum Profiler	4.33 KiB	4.33 KiB	0 B	0.00%	✅
Rum Recorder	24.48 KiB	24.48 KiB	0 B	0.00%	✅
Logs	56.21 KiB	56.31 KiB	+103 B	+0.18%	✅
Flagging	944 B	944 B	0 B	0.00%	✅
Rum Slim	123.05 KiB	123.18 KiB	+134 B	+0.11%	✅
Worker	23.63 KiB	23.63 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base CPU Time (ms)	Local CPU Time (ms)	𝚫%
addglobalcontext	N/A	0.0069	N/A
addaction	N/A	0.0227	N/A
adderror	N/A	0.0216	N/A
addtiming	N/A	0.0051	N/A
startview	N/A	0.0046	N/A
startstopsessionreplayrecording	N/A	0.0009	N/A
logmessage	N/A	0.0244	N/A

🧠 Memory Performance

Action Name	Base Memory Consumption	Local Memory Consumption	𝚫
addglobalcontext	N/A	32.25 KiB	N/A
addaction	N/A	107.46 KiB	N/A
addtiming	N/A	24.92 KiB	N/A
adderror	N/A	101.64 KiB	N/A
startstopsessionreplayrecording	N/A	29.34 KiB	N/A
startview	N/A	444.49 KiB	N/A
logmessage	N/A	102.87 KiB	N/A

🔗 RealWorld

[datadog-datadog-prod-us1]

⚠️ Tests

✨ Fix all issues with Cursor

⚠️ Warnings

🧪 53 Tests failed

createTaskQueue runs as many tasks as possible in a single idle callback from Chrome Headless 139.0.0.0 (Linux 0.0.0) (Datadog) (Fix with Cursor)

Error: Jasmine Clock was unable to install over custom global timer functions. Is the clock already installed?
    at <Jasmine>
    at mockClock (/go/src/github.com/DataDog/browser-sdk/packages/core/test/emulate/mockClock.ts:12:9 <- /tmp/_karma_webpack_629274/commons.js:145444:19)
    at UserContext.<anonymous> (/go/src/github.com/DataDog/browser-sdk/packages/core/src/tools/taskQueue.spec.ts:18:28 <- /tmp/_karma_webpack_629274/commons.js:122567:71)
    at <Jasmine>

createTaskQueue runs some tasks in case of timeout from Chrome Headless 139.0.0.0 (Linux 0.0.0) (Datadog) (Fix with Cursor)

Error: Jasmine Clock was unable to install over custom global timer functions. Is the clock already installed?
    at <Jasmine>
    at mockClock (/go/src/github.com/DataDog/browser-sdk/packages/core/test/emulate/mockClock.ts:12:9 <- /tmp/_karma_webpack_629274/commons.js:145444:19)
    at UserContext.<anonymous> (/go/src/github.com/DataDog/browser-sdk/packages/core/src/tools/taskQueue.spec.ts:42:28 <- /tmp/_karma_webpack_629274/commons.js:122585:71)
    at <Jasmine>

httpRequest HttpRequestEvent observable should report failure for failing requests from Chrome Headless 139.0.0.0 (Linux 0.0.0) (Datadog) (Fix with Cursor)

Error: Timeout - Async function did not complete within 5000ms (set by jasmine.DEFAULT_TIMEOUT_INTERVAL)
    at <Jasmine>

View all

ℹ️ Info

❄️ No new flaky tests detected

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