Replace onAttach / onDetach context event pair with onUpdate(before, after)

[mcculls]

Motivation

Reduces event cost while allowing listeners to detect the difference between updates to/from root and those updating from one non-root context to another.

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Jira ticket: [PROJ-IDENT]

[datadog-datadog-us1-prod]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 56.66% (-0.30%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: c0c3c75 | Docs | Datadog PR Page | Give us feedback!}

[dd-octo-sts]

🟡 Java Benchmark SLOs — Performance SLO warning (near threshold)

Suite	Status
Startup	🟡 warning

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.91 s	14.66 s	[+0.9%; +2.6%] (maybe worse)
startup:insecure-bank:tracing:Agent	13.65 s	13.75 s	[-1.5%; +0.1%] (no difference)
startup:petclinic:appsec:Agent	17.37 s	17.33 s	[-0.6%; +1.0%] (no difference)
startup:petclinic:iast:Agent	17.37 s	17.50 s	[-1.6%; +0.2%] (no difference)
startup:petclinic:profiling:Agent	17.28 s	17.41 s	[-1.9%; +0.5%] (no difference)
startup:petclinic:sca:Agent	17.48 s	16.65 s	[+0.6%; +9.3%] (maybe worse)
startup:petclinic:tracing:Agent	16.06 s	16.62 s	[-7.6%; +0.9%] (no difference)

Commit: c0c3c753 · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.