Make Live Debugger per-second budgets configurable

[watson]

Motivation

Allow Live Debugger users to tune per-second backpressure limits without changing the runtime defaults.

Changes

Add new DD_DEBUGGER.init() options to configure:

• the global snapshot per-second budget
• the default snapshot per-probe per-second budget
• the default non-snapshot per-probe per-second budget

Wire those options into the debugger probe budget logic and reset them when the debugger transport is reset. Add unit tests covering the configurable global snapshot limit and configurable per-probe snapshot/non-snapshot limits.

Test instructions

1. Run yarn test:unit --spec packages/debugger/src/domain/api.spec.ts
2. Run yarn test:unit --spec packages/debugger/src/domain/probes.spec.ts
3. In packages/debugger/src/entries/main.ts, verify that DebuggerInitConfiguration exposes:
   • maxSnapshotsPerSecondGlobally
   • maxSnapshotsPerSecondPerProbe
   • maxNonSnapshotsPerSecondPerProbe
4. In packages/debugger/src/domain/probes.ts, verify those values are used as the runtime defaults when probe-specific sampling is not set.

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]

• Add Live Debugger lifetime event budgets #4510
• Make Live Debugger per-second budgets configurable #4509 👈 (View in Graphite)
• Add Live Debugger package #4449 : 4 other dependent PRs (#4480 , #4503 , #4508 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	0.0146	+14.96%
RUM - add error	0.0166	0.0122	-26.51%
RUM - add timing	0.0006	0.0008	+33.33%
RUM - start view	0.0144	0.0152	+5.56%
RUM - start/stop session replay recording	0.0012	0.0012	0.00%
Logs - log message	0.0268	0.0223	-16.79%

🧠 Memory Performance

Action Name	Base Memory Consumption	Local Memory Consumption	𝚫
RUM - add global context	38.44 KiB	38.91 KiB	+479 B
RUM - add action	69.11 KiB	68.68 KiB	-440 B
RUM - add timing	36.85 KiB	37.64 KiB	+811 B
RUM - add error	69.34 KiB	69.21 KiB	-132 B
RUM - start/stop session replay recording	41.08 KiB	41.36 KiB	+294 B
RUM - start view	484.32 KiB	488.17 KiB	+3.85 KiB
Logs - log message	54.85 KiB	63.72 KiB	+8.87 KiB

🔗 RealWorld

[datadog-datadog-prod-us1]

🎉 All green!

❄️ No new flaky tests detected
🧪 All tests passed

🎯 Code Coverage (details)
• Patch Coverage: 80.00%
• Overall Coverage: 77.06% (+0.00%)

_{This comment will be updated automatically if new data arrives.
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