feat: add 7 alt-chart bar builders (B19) (#220)
Adds seven information-driven bar builders to the **Alt-Chart Bars** family, the final batch of the family-deepening run. Indicator count **507 → 514**.
## Builders
All implement the `BarBuilder` trait (`update(Candle) -> Vec<Bar>`), emitting a data-dependent number of completed bars per candle.
| Builder | Driver | Bar fields |
|---------|--------|-----------|
| `RangeBars` | close | open, close, direction |
| `TickBars` | OHLCV | open, high, low, close, volume |
| `VolumeBars` | OHLCV | open, high, low, close, volume |
| `DollarBars` (Lopez de Prado) | OHLCV | + dollar |
| `ImbalanceBars` | OHLC | + imbalance, direction |
| `RunBars` | OHLC | + length, direction |
| `ThreeLineBreakBars` | close | open, close, direction |
## Touchpoints
Seven core modules (each with full unit tests), `mod.rs`/`lib.rs` (builders counted, bar element types on their own re-export lines), README family rows, Python/Node/WASM hand-written bindings for the variable-length output (Python tuples + `(k, N)` ndarray; Node `Vec<object>`; WASM array of objects), the `bar_builder_update_candle` fuzz target, dedicated Python + Node tests, the `BAR_BUILDERS` completeness exclusion, and CHANGELOG.
## Verification
- `cargo test -p wickra-core --lib` — 4207 passed
- `cargo test -p wickra-core --doc` — 464 passed
- `cargo clippy --workspace --all-targets --all-features -- -D warnings` — clean
- `npm test` (node) — 584 passed
- `pytest` (python) — 957 passed
kingchenc
e5305ffa94