v0.8.7: Replace periodic ResyncInterval with Kahan compensated summation

Comprehensive refactor across all indicators replacing the periodic
ResyncInterval-based drift correction (every 1000 ticks recalculate
from scratch) with Kahan compensated summation for running sums.

Key changes:
- Remove ResyncInterval constants and TickCount fields from all State records
- Add Kahan compensation fields (SumComp, SumSqComp, etc.) to State records
- Replace naive sum += val - removed with Kahan delta pattern
- Remove Resync()/RecalculateSum() methods that did O(N) recalculation
- Update batch/SIMD paths to use Kahan compensation instead of resync loops
- IIR filters (EMA, REMA, RGMA) simplified: inherently self-correcting
- Version bump to 0.8.7
- Build system: README version stamping via Directory.Build.props
- Minor doc/test tolerance adjustments for new numerical characteristics

Affected modules: channels, core, cycles, dynamics, errors, momentum,
oscillators, statistics, trends_FIR, trends_IIR, volatility, volume

lib/core/tseries/tseries.cs

@@ -213,6 +213,9 @@ public class TSeries : IReadOnlyList<TValue>, ITValuePublisher
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public void Add(DateTime time, double value, bool isNew = true) => Add(new TValue(time, value), isNew);
 
+    /// <summary>
+    /// Adds a sequence of raw <see langword="double"/> values with fabricated timestamps.
+    /// </summary>
     /// <remarks>
     /// <b>Synthetic timestamps:</b> Each element receives a fabricated timestamp starting at
     /// <see cref="DateTime.UtcNow"/> (captured once at call time) and incrementing by one minute