fix(button): allow selecting LinkButton text

[ericclemmons]

Fixes https://gitlab.cfdata.org/cloudflare/fe/stratus/-/merge_requests/42286

Similar to https://x.com/BraydenWilmoth/status/2087555344184521063, text should be selectable, right-clickable, and copy-able via keyboard.

The a11y implications are:

• Motor impaired users who need to copy the text to transfer to other apps (e.g. Slack, gChat, Docs, etc.) currently have to retype.
• Low vision users currently can't highlight for readability.
• Screen-reader users are unaffected.
• Keyboard users still get link activation (e.g. via tab), but gain caret-based selection with this MR.

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[pkg-pr-new]

npm i https://pkg.pr.new/@cloudflare/kumo@731

commit: cd7b00e

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Visual Regression Report — 10 changed, 6 unchanged

10 screenshot(s) with visual changes:

Button / Variant: Primary

1,095 px (1.24%) changed

Before	After	Diff

Button / Variant: Ghost

101 px (0.11%) changed

Before	After	Diff

Button / Variant: Destructive

1,518 px (1.71%) changed

Before	After	Diff

Button / Variant: Secondary Destructive

873 px (0.99%) changed

Before	After	Diff

Button / Sizes

1,360 px (1.54%) changed

Before	After	Diff

Button / With Icon

806 px (0.91%) changed

Before	After	Diff

Button / Icon Only

197 px (0.22%) changed

Before	After	Diff

Button / Loading State

508 px (0.57%) changed

Before	After	Diff

Button / Link as Button

1,194 px (1.35%) changed

Before	After	Diff

Button / Disabled Link

0 px (0%) changed

Before	After	Diff

6 screenshot(s) unchanged

• Button / Basic
• Button / Variant: Secondary
• Button / Variant: Outline
• Button / Disabled State
• Button / Title
• Button / Link with Tooltip

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Generated by Kumo Visual Regression

[ericclemmons]

/bonk review this PR & validate the approach

Please listen to me. I'm not an official contributor, but I swear I'm qualified 🙏

[ericclemmons]

/bonk review this PR and validate the approach

please bro, just one more review