v0.3.0

Storage release. Fixes a bug that silently destroyed the evidence the project
exists to preserve.

Fixed

• Frame events no longer evict every other kind of evidence. The store was
  one shared 5,000-event buffer. FrameCollector writes an event per frame, so
  at 60fps frames filled the entire buffer in about 83 seconds and then evicted
  everything older — the exceptions, network requests and logs you were actually
  chasing. Two minutes into a session, the exception from minute one was gone.
  Each category now has its own ring buffer, so a noisy stream can only evict
  itself. Defaults: 3,000 logs, 1,000 exceptions, 1,000 network, 1,000 frames,
  500 system, overridable through the RuntimeStore constructor.
• Insertion is O(1). The buffer was trimmed with splice(0, n) on every
  insert past capacity, copying the whole array 60 times a second inside the
  tool meant to diagnose performance problems. Replaced with a circular buffer:
  200,000 events went from 9,943ms to 81ms, a 122x improvement.

Added

• runtime_status now reports retention: per-category capacity, how many
  events are retained, how many were evicted, and the timestamp of the oldest
  event still held. A capped buffer is fine; a silently capped one leaves an
  agent reasoning over truncated history without knowing it.
• CATEGORIES is exported from core/events.ts as a runtime value, with the
  Category type derived from it so the two cannot drift.

Compatibility

No tool renamed, removed, or reshaped. RuntimeStore.query() returns the same
most-recent-first ordering, now merged across the per-category buffers.
runtime_status.retention is additive.