feat: expand rust parity, wasm exports, and api conformance

Move several hot Python analysis paths to Rust-backed helpers. This adds Rust implementations for backtest strategy signal generation and the core portfolio loop, options and futures payoff aggregation, Greeks aggregation, ratio calculation, trade extraction, chunked close-only indicator runs, and forward-fill helpers. Wire the Python analysis and data modules to prefer these paths, and add coverage for the new batch fast path.

Expand the WASM package to export WMA, ADX, and MFI from ferro_ta_core, refresh the Node examples, benchmarks, and README, and add a Node-vs-Python conformance test so the browser and node surface stays aligned with the main Python package.

Introduce a generated cross-surface API manifest in docs/, along with scripts to rebuild and verify it from source exports. Enforce manifest freshness in the Python and WASM CI workflows so release candidates catch surface drift before push.

python/ferro_ta/analysis/cross_asset.py

@@ -40,6 +40,7 @@ from __future__ import annotations
 import numpy as np
 from numpy.typing import ArrayLike, NDArray
 
+from ferro_ta._ferro_ta import ratio as _rust_ratio
 from ferro_ta._ferro_ta import relative_strength as _rust_rel_strength
 from ferro_ta._ferro_ta import rolling_beta as _rust_rolling_beta
 from ferro_ta._ferro_ta import spread as _rust_spread
@@ -162,11 +163,7 @@ def ratio(
     >>> list(ratio(a, b))
     [2.0, 3.0, 3.0]
     """
-    av = _to_f64(a)
-    bv = _to_f64(b)
-    with np.errstate(divide="ignore", invalid="ignore"):
-        result = np.where(bv == 0, np.nan, av / bv)
-    return result
+    return _rust_ratio(_to_f64(a), _to_f64(b))
 
 
 # ---------------------------------------------------------------------------