fix(amazonq): update diff view with syntax highlights and proper new file view#5679

rli merged 9 commits intofeature/q-lsp-chataws/aws-toolkit-jetbrains:feature/q-lsp-chatfrom

samgst/q-lsp-chat-showDiffWithHighlightingaws/aws-toolkit-jetbrains:samgst/q-lsp-chat-showDiffWithHighlightingCopy head branch name to clipboard