[kernel-1116] remaining cdp handlers

[archandatta]

Final layer of the CDP monitor split. Replaces the no-op dispatchEvent stub with the full handler implementation and completes the test suite. Merges cleanly on top of #214

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Note

Medium Risk
Adds full CDP event dispatch/handling and emits richer network/page interaction events (including headers and optional response bodies), which can affect event volume and expose sensitive data to downstream consumers.

Overview
Completes the CDP monitor split by replacing the no-op dispatchEvent stub with a full handler implementation that publishes console, page/navigation, target, interaction binding, timeline layout-shift, and detailed network request/response events (including optional truncated response bodies for textual resources).

Improves lifecycle/computed-state correctness by handling redirects without inflating pending counters, ignoring subframe lifecycle events for main-frame settling logic, and standardizing published event timestamps to microseconds (including screenshots and monitor lifecycle events). Adds an extensive test suite covering these handlers, rate-limiting of binding events, auto-attach/attach-existing-targets flows, and the redirect/subframe edge cases; updates API wiring to pass a slog logger into cdpmonitor.New.

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