refactor(remote-config): replace kPreUpdate with batch handler API (DEBUG-4402)

[watson]

What does this PR do?

• Removes the leaky kPreUpdate hook from RemoteConfigManager and replaces it with a first-class batch handler API (setBatchHandler/removeBatchHandler) that receives an explicit transaction (ack/error/markHandled).
• Introduces explicit RC product subscription via subscribeProducts(...products) / unsubscribeProducts(...products) and makes setProductHandler / removeProductHandler subscribe/unsubscribe for clarity.
• Wires AppSec/WAF RC updates to the new batch transaction API and centralizes ASM/WAF RC product names in appsec/rc-products.js.

Motivation

kPreUpdate exposed internal mutable state and blurred responsibility between RC internals and consumers. WAF needs to reconcile multiple products in one logical update, so the new batch API provides a safer and clearer surface.

[watson]

• feat(debugger): add Remote Enablement support #7137
• refactor(remote_config): move capability registration to feature modules #7127
• refactor(remote_config): move appsec-specific logic to appsec folder #7122
• refactor(remote-config): replace kPreUpdate with batch handler API (DEBUG-4402) #7121 👈 (View in Graphite)
• master

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[pr-commenter]

Benchmarks

Benchmark execution time: 2026-01-06 19:18:40

Comparing candidate commit 0bc9468 in PR branch watson/refactor-rc with baseline commit 2681a5e in branch master.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 287 metrics, 33 unstable metrics.

[codecov]

Codecov Report

❌ Patch coverage is 93.33333% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.52%. Comparing base (2681a5e) to head (0bc9468).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
packages/dd-trace/src/remote_config/manager.js	90.47%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7121      +/-   ##
==========================================
+ Coverage   84.51%   84.52%   +0.01%     
==========================================
  Files         525      526       +1     
  Lines       22492    22537      +45     
==========================================
+ Hits        19008    19049      +41     
- Misses       3484     3488       +4     

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[github-actions]

Overall package size

Self size: 4.4 MB
Deduped: 5.22 MB
No deduping: 5.22 MB

Dependency sizes

| name | version | self size | total size | |------|---------|-----------|------------| | import-in-the-middle | 2.0.0 | 68.46 kB | 797.03 kB | | dc-polyfill | 0.1.10 | 26.73 kB | 26.73 kB |

_{🤖 This report was automatically generated by heaviest-objects-in-the-universe}

[BridgeAR]

It seems like a good improvement to separate things by product. Just left a few minor suggestions

[BridgeAR]

LGTM, just left a question