feat: async session manager

[mormubis]

Motivation

The Session Manager Revamp (SMR) will require our session manager to operate asynchronously and postpone the SDK initialization until the session is ready.

Changes

onReady callback in session manager that propagates through all places using the start of the session.

Test instructions

TBD

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	164.29 KiB	164.50 KiB	+216 B	+0.13%	✅
Rum Profiler	4.33 KiB	4.33 KiB	0 B	0.00%	✅
Rum Recorder	20.01 KiB	20.01 KiB	0 B	0.00%	✅
Logs	56.10 KiB	56.24 KiB	+143 B	+0.25%	✅
Flagging	944 B	944 B	0 B	0.00%	✅
Rum Slim	121.50 KiB	121.71 KiB	+213 B	+0.17%	✅
Worker	23.63 KiB	23.63 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base CPU Time (ms)	Local CPU Time (ms)	𝚫%
RUM - add global context	0.0039	0.0063	+61.54%
RUM - add action	0.0121	0.017	+40.50%
RUM - add error	0.0138	0.0169	+22.46%
RUM - add timing	0.0028	0.004	+42.86%
RUM - start view	0.0031	0.006	+93.55%
RUM - start/stop session replay recording	0.0007	0.0015	+114.29%
Logs - log message	0.0159	0.0277	+74.21%

🧠 Memory Performance

Action Name	Base Memory Consumption	Local Memory Consumption	𝚫
RUM - add global context	27.01 KiB	25.88 KiB	-1.13 KiB
RUM - add action	52.22 KiB	50.97 KiB	-1.25 KiB
RUM - add timing	24.95 KiB	24.58 KiB	-380 B
RUM - add error	55.47 KiB	54.22 KiB	-1.24 KiB
RUM - start/stop session replay recording	25.44 KiB	24.82 KiB	-634 B
RUM - start view	422.98 KiB	424.35 KiB	+1.36 KiB
Logs - log message	48.96 KiB	47.15 KiB	-1.81 KiB

🔗 RealWorld

[datadog-official]

⚠️ Tests

✨ Fix all issues with Cursor

⚠️ Warnings

🧪 10 Tests failed

preStartRum configuration validation should start when the configuration is valid from Chrome 139.0.0.0 (Android 10) (Datadog) (Fix with Cursor)

Error: Expected spy unknown to have been called.
    at <Jasmine>
    at UserContext.<anonymous> (webpack:///packages/rum-core/src/boot/preStartRum.spec.ts:72:29 <- /tmp/_karma_webpack_487361/commons.js:71632:35)
    at <Jasmine>

preStartRum init plugins plugins can edit the init configuration prior to validation from Chrome 139.0.0.0 (Android 10) (Datadog) (Fix with Cursor)

TypeError: Cannot read properties of undefined (reading 'args')
    at UserContext.<anonymous> (webpack:///packages/rum-core/src/boot/preStartRum.spec.ts:517:48 <- /tmp/_karma_webpack_487361/commons.js:71935:56)
    at <Jasmine>

preStartRum init trackViews mode when auto before init startView should be handled after init from Chrome 139.0.0.0 (Android 10) (Datadog) (Fix with Cursor)

Error: Expected undefined to equal Object({ relative: 17299, timeStamp: 1768390264980 }).
    at <Jasmine>
    at UserContext.<anonymous> (webpack:///packages/rum-core/src/boot/preStartRum.spec.ts:344:52 <- /tmp/_karma_webpack_487361/commons.js:71819:62)
    at <Jasmine>

View all

ℹ️ Info

❄️ No new flaky tests detected

🎯 Code Coverage
• Patch Coverage: 75.47%
• Overall Coverage: 77.20% (-0.08%)

View detailed report

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