feat(amazon lsp): add copyToClipboard implementation

[opieter-aws]

Problem

There was no implementation for the copyToClipboard message received from LSP for Amazon Q. The functionality did work because of the MynahUI implementation, but for UI consistency to consider edge cases with webview clipboard, we decided to handle it explicitly.

Solution

Call the copyToClipboard function and add unit tests

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[github-actions]

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