C29 compile/unit seam, task 3 of the self-description plan: every
aura-std NodeSchema literal threads its one-line doc. Four texts were
corrected against the actual eval/finalize semantics rather than taken
from the plan table verbatim: Delay is a lag-N register (not one-step),
GatedRecorder flushes an ungated final row at finalize, Latch is a
level-sensitive set/reset register (captures no input), SeriesReducer
emits its single summary row at finalize (not per cycle).
Gate: cargo build -p aura-std --lib clean; full std test run follows at
the all-crates gate once strategy/backtest/engine thread their sites
(the earlier per-crate test gate was unsatisfiable in isolation --
std's dev-deps pull crates whose sites belong to later tasks).
refs #316
The two genuinely-missing arithmetic primitives (Mul = two-stream f64 product,
Sqrt = one-input f64 root, negatives clamped to 0). They are the building blocks
for the volatility stop as a composition (rolling EWMA stddev), replacing the
fused VolStop node. Also corrects plan 0066 Task 3 (the VolStop removal must
migrate its stage1_r_e2e.rs caller — a false premise the implementer caught).
refs #117#119