16c0639f0c
Completes the F6 family (Trend strength) end to end: - Rust core: aroon_oscillator.rs (AroonUp - AroonDown, one-line trend gauge), vortex.rs (Vortex Indicator VI+/VI- with the VortexOutput struct), mass_index.rs (Dorsey's range-expansion sum of the EMA-of-range ratio). Each with a full Indicator impl, runnable doctest and reference / saturation / warmup / reset / batch==streaming tests. - Python: PyAroonOscillator / PyVortex / PyMassIndex PyO3 classes + module registration + .pyi stubs (defaults Aroon=14, Vortex=14, MassIndex=(9,25)). - Node: explicit AroonOscillatorNode, VortexNode (with VortexValue object) and MassIndexNode; index.d.ts and index.js updated. - WASM: WasmAroonOscillator, WasmVortex, WasmMassIndex. - Wiki: Indicator-AroonOscillator/Vortex/MassIndex.md plus rows in Indicators-Overview.md and entries in Home.md. cargo fmt + clippy (core/wickra/data/wasm/node) clean; 320 core tests, 25 data tests and 45 doctests green.