v0.2.0

Minor Changes

• 190865b: Add runSmallSignalAcSweep / runSmallSignalAcSweepAsync — a worker-hostable
  driver for the linearized small-signal AC analysis.

  runSmallSignalAc is the exact, ngspice-cross-validated transfer function, but
  its signature suits an in-process caller: it takes a live SimEngine, runs the
  whole frequency loop atomically, and offers no progress callback or
  cancellation. This driver adds those three things for a UI worker — a
  structured-cloneable circuit in, one onPoint per frequency, and cooperative
  shouldCancel — by composing runSmallSignalAc unchanged, one chunk of
  frequencies at a time with a macrotask yield between chunks. The chunking
  re-solves the (deterministic) operating point per chunk and is proven
  bit-identical to a single call. Exported from brownout/analysis.