chore: rename trackLatency to trackDuration on LDGraphTracker

[jsonbailey]

Summary

• Renames trackLatency() → trackDuration() on the LDGraphTracker interface and LDGraphTrackerImpl class to align with the existing trackDuration naming on LDAIConfigTracker
• Updates the event key from $ld:ai:graph:latency to $ld:ai:graph:duration:total per the updated AIGRAPHTRACK spec
• Updates all tests to match the new method name and event key

Test plan

• All 144 unit tests pass (yarn workspace @launchdarkly/server-sdk-ai test)
• Lint passes clean
• Build succeeds

🤖 Generated with Claude Code

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Note

Medium Risk
Public API rename plus a telemetry event-key change may break downstream callers and dashboards if they aren’t updated, but the implementation change is small and localized.

Overview
Renames the graph timing API from trackLatency(durationMs) to trackDuration(durationMs) on LDGraphTracker and LDGraphTrackerImpl, including updated warnings and docs.

Switches the emitted metric event from $ld:ai:graph:latency to $ld:ai:graph:duration:total, and updates unit tests to assert the new method name and event key.

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[github-actions]

@launchdarkly/js-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 25623 bytes
Compressed size limit: 29000
Uncompressed size: 125843 bytes

[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 37607 bytes
Compressed size limit: 38000
Uncompressed size: 207149 bytes

[github-actions]

@launchdarkly/browser size report
This is the brotli compressed size of the ESM build.
Compressed size: 179269 bytes
Compressed size limit: 200000
Uncompressed size: 830289 bytes

[github-actions]

@launchdarkly/js-client-sdk size report
This is the brotli compressed size of the ESM build.
Compressed size: 31722 bytes
Compressed size limit: 34000
Uncompressed size: 113100 bytes

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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