chore: remove uncontroversial ts-expect-error suppressions

[willeastcott]

Summary

Three pure typing fixes that let us drop 12 of the existing // @ts-expect-error markers in pcui (38 → 26), with no runtime change and no public-API expansion.

• Widen attachElement in the React wrapper base (src/components/Element/component.tsx) to (HTMLElement | SVGElement | null, any?) so it matches React's callback ref contract. The body already short-circuits on null, and the wider DOM type covers Spinner's <svg>. Matched in the LabelGroup override. Drops the suppression above every <… ref={this.attachElement} /> in Button, Canvas, ColorPicker, Container, Element, GradientPicker, InfoBox, Label, Spinner (9 sites).
• Match ColorPicker.set values to the IBindable contract (src/components/ColorPicker/index.ts) — the parameter was declared Array<number> but the body already handles array-of-arrays (the Array.isArray(value) branch). Changed to Array<any> to match the interface (2 sites).
• Annotate comboItems as Record<number, string> in src/components/GradientPicker/index.ts so the dynamic comboItems[3] = 'Legacy' assignment type-checks (1 site).

The remaining 26 suppressions all require a real API decision (visibility widening, dynamic-property data smell, or interface mismatches) and are intentionally left out of this PR.

Test plan

• npm run build:types — tsc clean on both tsconfig.json and react/tsconfig.json (the removed markers were each suppressing an actual error before; tsc would fail if any deleted one weren't needed)
• npm run lint:js — clean
• npm run build:es6 — Rollup build green
• npm test — 50/50 pass

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR removes several TypeScript suppression comments by aligning React wrapper ref typing and a couple of component typings with existing usage and interfaces.

Changes:

• Widens React wrapper attachElement signatures to support callback refs, null, and SVG elements.
• Removes now-unneeded @ts-expect-error comments from wrapper render refs.
• Adjusts ColorPicker.values typing and GradientPicker combo item typing.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/components/Element/component.tsx	Widens base attachElement callback ref type and removes base render suppression.
src/components/LabelGroup/component.tsx	Mirrors the widened attachElement override signature.
src/components/Button/component.tsx	Removes ref suppression.
src/components/Canvas/component.tsx	Removes ref suppression.
src/components/ColorPicker/component.tsx	Removes ref suppression.
src/components/ColorPicker/index.ts	Aligns values setter with IBindable array contract.
src/components/Container/component.tsx	Removes ref suppression.
src/components/GradientPicker/component.tsx	Removes ref suppression.
src/components/GradientPicker/index.ts	Adds a numeric record type for curve type combo items.
src/components/InfoBox/component.tsx	Removes ref suppression.
src/components/Label/component.tsx	Removes ref suppression.
src/components/Spinner/component.tsx	Removes SVG ref suppression.

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