Adds the first-tick bootstrap diff: ToLoadNear for the (2*near+1)^2 inner
window, ToLoadFar for the outer annulus up to FarRadius. Uses Chebyshev
distance, matching existing Recenter convention.
Also renames the single-tier RecenterTo → RecenterToSingleTier to free
the canonical name for the upcoming two-tier overload (T5). Updates
StreamingRegionTests and StreamingController to call the renamed method.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Code review on commit 7fd9c82 flagged that the test asserted NearRadius,
FarRadius, CenterX, CenterY but not the load-bearing alias
Radius == FarRadius. That alias is what makes the existing hysteresis
math (Radius+2 unload threshold) correctly target the far-tier boundary.
Future typos would silently break far-tier hysteresis.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Add NearRadius/FarRadius properties and a four-arg constructor
(centerX, centerY, nearRadius, farRadius). Radius is set to farRadius
so existing hysteresis math (unload threshold = Radius+2) uses the
outer ring as the bookkeeping boundary. Old three-arg constructor
becomes a thin wrapper: this(cx, cy, radius, radius) — no behaviour
change, 25 pre-existing streaming tests still pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
