fix: isolate user overlay callbacks in draw path

[NemeZZiZZ]

Problem

The three overlay figure callbacks — createPointFigures, createXAxisFigures,
createYAxisFigures — are user-supplied code (custom overlay templates). They are
invoked during drawing with no isolation:

// src/view/OverlayView.ts:574
return o.createPointFigures?.({ chart, overlay: o, coordinates, bounding, xAxis, yAxis }) ?? []
// src/view/OverlayXAxisView.ts:75 / src/view/OverlayYAxisView.ts:83 — same shape

If the callback throws, the exception propagates up through _drawOverlay →
updatePane → _layout, breaking the whole draw pass. A realistic case: overlays
restored from persisted state (local storage / cloud) can end up with an invalid
point set, and a custom template that assumes valid input throws
(TypeError: Cannot read properties of undefined (reading 'length') at
createPointFigures). One broken overlay then breaks drawing for the chart, and —
combined with the layout pending flag not being released on throw — freezes it entirely.

Indicator callbacks already have this isolation: IndicatorImp.calcImp
(src/component/Indicator.ts) wraps the user calc callback in try { … } catch { … },
so a broken indicator fails alone instead of breaking the chart. The overlay
callbacks deserve the same treatment.

Fix

Wrap each of the three invocations and fall back to an empty figure list:

-    return o.createPointFigures?.({ chart, overlay: o, coordinates, bounding, xAxis, yAxis }) ?? []
+    try {
+      return o.createPointFigures?.({ chart, overlay: o, coordinates, bounding, xAxis, yAxis }) ?? []
+    } catch {
+      return []
+    }

Same for createXAxisFigures (OverlayXAxisView) and createYAxisFigures
(OverlayYAxisView). A throwing overlay now simply draws nothing for that pass
instead of breaking the draw pipeline — mirroring the calcImp behaviour for indicators.

Verification

• pnpm code-lint — pass (154 files, no fixes)
• pnpm type-check — pass
• pnpm build-esm — pass
• Manual repro on main: registerOverlay a template whose createPointFigures
  throws, create one, trigger a redraw — drawing breaks; with this patch the rest
  of the chart keeps drawing correctly and the overlay is skipped.

Notes

• The catch is intentionally silent, matching the existing calcImp isolation
  style. Logging the error could be added separately if wanted.
• Companion fix: releasing _layoutPending when _layout() throws (fix: reset layout pending flag when layout throws #832) —
  each addresses one half of the "one bad overlay freezes the chart" failure.