Add finance charting surface

[Alek99]

Summary

• add native candlestick and OHLC marks plus a composable finance-chart container
• add OHLCV volume panes, moving averages, Bollinger bands, VWAP/anchored VWAP, volume profiles, RSI, MACD, and Stochastic
• add portfolio/risk layers for equity and drawdown plus return distributions with VaR/CVaR markers
• add serializable position, forecast, measurement, volume, and chart-pattern layers
• preserve finance layer/tool payloads through the Reflex adapter
• document the finance roadmap and add focused API, payload, adapter, and renderer regressions

Why

XY needs a Python-native finance surface that composes with the existing chart and Reflex APIs without overloading the base candlestick mark. Studies, drawings, panes, and tool state remain independent layers over the same renderer and binary transport.

User and developer impact

Python users can compose finance charts from the public XY component API. Reflex users can publish state-dependent finance figures while keeping large market arrays out of Reflex state.

The pre-existing example applications are unchanged from main; this PR contains no example-app or notebook changes.

Validation

• focused finance, example-compatibility, adapter, API-parity, and type-surface suites — 162 passed, 1 skipped
• restored Reflex showcase compiles successfully in production mode
• Ruff checks and formatting pass
• focused headless-browser toolbar regression passes

Draft scope

The core Tier-1 finance surface is present. Interactive drawing creation/editing, persistence, session-aware axes, finance-bar streaming, and broader indicator/alternative-chart coverage remain follow-up work documented in docs/quant-finance-roadmap.md.

This supersedes #1, which GitHub could not reopen after its head branch was force-pushed/recreated.

[coderabbitai]

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[greptile-apps]

Greptile Summary

The PR adds a composable finance-charting surface across the Python API, binary payload pipeline, Reflex adapter, and browser renderer.

• Adds candlestick/OHLC marks, finance studies, drawings, oscillator and volume panes, and portfolio/risk layers.
• Extends payload and adapter support for finance-specific traces, layers, and tool state.
• Updates the short-chart pane allocator so the main plot, gaps, and lower panes stay within the available plot rectangle.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains; the prior pane-overflow issue is fixed by allocating the main plot, collapsed gaps, and lower panes from one bounded height budget, with a browser regression covering the reported three-pane case.

Important Files Changed

Filename	Overview
js/src/50_chartview.ts	Adds finance-layer rendering and a bounded pane allocator; the previous three-pane short-chart overflow is fixed by shrinking gaps and pane heights within the available budget.
js/src/40_gl.ts	Adds dedicated WebGL candlestick/OHLC shaders and fixed attribute bindings.
js/src/57_layers.ts	Adds finance-layer rendering for studies, drawings, volume panes, and oscillators.
python/xy/finance.py	Implements finance components, indicators, risk calculations, and serializable layer specifications.
python/xy/_payload.py	Extends binary payload emission for the new finance mark geometry and layer metadata.
python/reflex_xy/assets/XYChart.jsx	Preserves and forwards finance chart layers and tool payloads through the Reflex client adapter.
tests/test_ui_issue_regressions.py	Adds a browser regression proving three lower panes remain ordered, visible, and contained in a 150 px plot budget.

_{Reviews (3): Last reviewed commit: "Keep finance panes within short charts" | Re-trigger Greptile}

[codspeed-hq]

Merging this PR will not alter performance

✅ 109 untouched benchmarks
⏩ 2 skipped benchmarks¹

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_{Comparing codex/finance-charting-surface (92e092e) with main (e6f367f)}

Footnotes

1. 2 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩