feat: add copy feedback to preferences sheet

[vedayeminedi]

Linked issue

Closes #790

What this PR does

Adds explicit visual feedback when copying the configuration summary from the Preferences sheet.

Changes

• Replaced the boolean copy state with a copyStatus state (idle, success, error).
• Displays a success message ("✓ Copied!") after a successful copy operation.
• Displays an error message ("⚠ Copy failed") if the clipboard operation fails.
• Resets the feedback state after a short delay.
• Added focused tests covering both successful and failed clipboard copy scenarios.

Type of change

• ✨ New feature
• 🐛 Bug fix
• 💥 Breaking change
• 📚 Documentation update

[vercel]

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[vedayeminedi]

Hi @imDarshanGK, I verified the changes related to this PR by running the SettingsPanel test suite locally, and all tests passed. The failures shown in the full test suite appear to be from existing tests in Sidebar.test.jsx and UploadPanel.test.jsx, which are outside the scope of this PR. Please let me know if you'd like me to investigate anything further.

[imDarshanGK]

@vedayeminedi

[vedayeminedi]

Hi @imDarshanGK, I verified the frontend changes in this PR locally, and the SettingsPanel test suite passes successfully. This PR only modifies frontend/src/components/SettingsPanel.jsx and frontend/src/components/SettingsPanel.test.jsx. The failing CI check appears to be in the Backend (Python) workflow, which is outside the scope of these changes. Please let me know if you'd like me to investigate anything further.