ref(perf-detectors): Pass detector-specific settings to PerformanceDetector constructors

[kcons]

Previously, each PerformanceDetector received the full settings dict for all detector types and extracted its own config in __init__. This meant every detector had visibility into other detectors' configuration, even though none actually used it.

Now the caller extracts the specific detector's settings before instantiation, so each detector only receives its own config dict, and we can be confident configs are independent.

[cursor]

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