✨ Add browser debugger Capture Expressions

[watson]

Motivation

Add Capture Expressions support to the browser debugger so method probes can capture named expression results without enabling full snapshot capture.

Changes

• Add captureExpressions probe parsing/compilation for browser debugger probes.
• Evaluate Capture Expressions at the configured method phase (ENTRY or EXIT) and serialize them under captures.entry.captureExpressions or captures.return.captureExpressions.
• Treat Capture Expression probes as snapshot-producing for sampling, global limits, stack capture, and lifetime budgets.
• Reject Delivery API probes that combine captureSnapshot with captureExpressions.
• Add a shared mergeArrays utility in browser-core for optional array merging.
• Add unit coverage for compilation, invalid expressions, delivery filtering, entry/return/throw evaluation, evaluation errors, limits, and rate limiting.

Test instructions

• yarn test:unit --spec packages/browser-core/src/tools/utils/arrayUtils.spec.ts --spec packages/browser-debugger/src/domain/template.spec.ts --spec packages/browser-debugger/src/domain/probes.spec.ts --spec packages/browser-debugger/src/domain/api.spec.ts --spec packages/browser-debugger/src/domain/deliveryApi.spec.ts
• yarn typecheck

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 browser debugger Capture Expressions #4731 👈 (View in Graphite)
• ♻️ Simplify debugger template evaluation #4730
• main

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[cit-pr-commenter-54b7da]

Bundles Sizes Evolution

📦 Bundle Name	Base Size	Local Size	𝚫	𝚫%	Status
Rum	171.86 KiB	171.86 KiB	0 B	0.00%	✅
Rum Profiler	7.88 KiB	7.88 KiB	0 B	0.00%	✅
Rum Recorder	21.21 KiB	21.21 KiB	0 B	0.00%	✅
Logs	54.31 KiB	54.31 KiB	0 B	0.00%	✅
Rum Slim	129.69 KiB	129.69 KiB	0 B	0.00%	✅
Worker	22.96 KiB	22.96 KiB	0 B	0.00%	✅

[datadog-datadog-prod-us1]

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 80.26%
• Overall Coverage: 76.75% (+0.03%)

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