Add a "Copied!" confirmation to the CopyButton component

[Meshmulla]

👋 Nice little UX polish task, perfect for a first contribution!

The idea

We have a CopyButton component (src/components/CopyButton.tsx) used to copy things like bridge addresses, asset codes, and API keys. Right now it copies to the clipboard but gives no visible confirmation, so users aren't always sure the copy worked.

Let's add a brief "Copied!" confirmation.

What we'd like

When the button is clicked and the copy succeeds:

• Briefly swap the icon/label to a check + "Copied!" for ~1.5 seconds, then revert
• Make it accessible: announce the change to screen readers (e.g. an aria-live="polite" region or an updated aria-label)
• Keep it smooth if clicked repeatedly (no flicker)

Where to look

• src/components/CopyButton.tsx — the component itself
• src/components/CopyButton.test.tsx — existing tests; please extend these
• Look for existing toast/tooltip primitives in src/components before adding anything new

Acceptance criteria

• Clicking shows a temporary "Copied!" state, then reverts automatically
• Works when clicked several times in a row without visual glitches
• Screen-reader users get feedback (accessible announcement)
• Confirmation text is translated via react-i18next
• CopyButton.test.tsx covers the new behavior

Getting started

npm install
npm run dev
npm run test        # or the project's test script

Comment here if you'd like a pointer on the clipboard mocking in tests — glad to help! ✨

[vrickish]

Hi maintainer, I would like to work on this issue.

[grantfox-oss]

🦊 GrantFox — @vrickish has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #2)
2. Your PR will be reviewed by the stellar-kracken maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign | FWC26 campaign!

@vrickish's PR #20 was approved and merged by @Meshmulla.

🏆 @vrickish: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (344 total points). Track your full progress on GrantFox.

👏 Great work, @vrickish! Keep contributing to stellar-kracken.