Switch debugger delivery to public ClientTokenAuth endpoint

[watson]

Motivation

Switch the debugger delivery API from the internal same-origin /api/ui/debugger/probe-delivery route (ValidUser session cookie auth) to the public /api/unstable/debugger/frontend/probes route (ClientTokenAuth). This is Stage 3 of the probe delivery redesign, enabling the browser SDK to fetch probes through the public Smart Edge route using the same RUM-style client token authentication model used by other Datadog frontend SDKs.

The backend route is already registered in debugger-delivery-api and allowlisted for ClientTokenAuth in Lambo.

Changes

packages/debugger/src/domain/deliveryApi.ts

• Endpoint path changed from /api/ui/debugger/probe-delivery to /api/unstable/debugger/frontend/probes
• Delivery URL is now constructed as https://api.{site}/... from the site config (defaults to datadoghq.com)
• Authentication changed from credentials: 'same-origin' (session cookies) to a dd-client-token request header
• Added proxy support: when set, the proxy origin replaces the computed API host (used by E2E tests and available for customer proxy setups)

packages/debugger/src/entries/main.ts

• Added proxy?: string to DebuggerInitConfiguration
• clientToken, site, and proxy are now forwarded to startDeliveryApiPolling

E2E test infrastructure

• Delivery mock endpoint moved from the base mock server to the intake server (since formatConfiguration already sets proxy: servers.intake.origin for all SDK configs)
• setDebuggerProbes moved from MockServerApp to IntakeServerApp
• E2E scenarios updated to call servers.intake.app.setDebuggerProbes

Test instructions

Unit tests:

yarn test:unit --spec packages/debugger/src/domain/deliveryApi.spec.ts

All debugger unit tests:

yarn test:unit --spec "packages/debugger/src/**/*.spec.ts"

To verify on staging: initialize the debugger SDK with a valid clientToken and applicationId, confirm that delivery polling requests go to https://api.datad0g.com/api/unstable/debugger/frontend/probes with a dd-client-token header (visible in the Network tab).

Checklist

• Tested locally
• Tested on staging
• Added unit tests for this change.
• Added e2e/integration tests for this change.
• Updated documentation and/or relevant AGENTS.md file

[watson]

• Default debugger version and embed build identity in snapshots #4511
• Default args and locals params in debugger snapshot hooks #4609
• Switch debugger delivery to public ClientTokenAuth endpoint #4480 👈 (View in Graphite)
• Add Live Debugger package #4449 : 4 other dependent PRs (#4503 , #4508 , #4509 and 1 other)
• Fix TanStack Router lint resolution in test app #4513
• main

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[cit-pr-commenter-54b7da]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	169.36 KiB	169.36 KiB	0 B	0.00%	✅
Rum Profiler	5.97 KiB	5.97 KiB	0 B	0.00%	✅
Rum Recorder	21.23 KiB	21.23 KiB	0 B	0.00%	✅
Logs	54.70 KiB	54.70 KiB	0 B	0.00%	✅
Rum Slim	127.69 KiB	127.69 KiB	0 B	0.00%	✅
Worker	22.99 KiB	22.99 KiB	0 B	0.00%	✅

🚀 CPU Performance

Action Name	Base CPU Time (ms)	Local CPU Time (ms)	𝚫%
RUM - add global context	0.0026	0.0021	-19.23%
RUM - add action	0.0127	0.0128	+0.79%
RUM - add error	0.0166	0.0118	-28.92%
RUM - add timing	0.0006	0.0007	+16.67%
RUM - start view	0.0144	0.0126	-12.50%
RUM - start/stop session replay recording	0.0012	0.001	-16.67%
Logs - log message	0.0268	0.017	-36.57%

🧠 Memory Performance

Action Name	Base Memory Consumption	Local Memory Consumption	𝚫
RUM - add global context	38.44 KiB	38.01 KiB	-439 B
RUM - add action	69.11 KiB	68.04 KiB	-1.07 KiB
RUM - add timing	36.85 KiB	36.85 KiB	+2 B
RUM - add error	69.34 KiB	68.94 KiB	-411 B
RUM - start/stop session replay recording	41.08 KiB	41.15 KiB	+75 B
RUM - start view	484.32 KiB	459.22 KiB	-25.10 KiB
Logs - log message	54.85 KiB	54.61 KiB	-252 B

🔗 RealWorld

[datadog-prod-us1-3]

🎉 All green!

❄️ No new flaky tests detected
🧪 All tests passed

🎯 Code Coverage (details)
• Patch Coverage: 75.00%
• Overall Coverage: 77.05% (-0.01%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 239ef70 | Docs | Datadog PR Page | Give us feedback!}

[chatgpt-codex-connector]

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