feat: add copy button to System Info panel (#9719)

## Summary

Adds a "Copy System Info" button next to the System Info heading in
Settings > About. Copies all system and device details as markdown text
for easy pasting into Slack or Notion.
<img width="1175" height="725" alt="Screenshot 2026-03-10 at 1 30 51 PM"
src="https://github.com/user-attachments/assets/6a091b6d-2246-4dc7-bc1d-8b5ebc2f9f9b"
/>


## Test plan
- Open Settings > About
- Click "Copy System Info" button
- Paste into Slack/Notion and verify formatting

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9719-feat-add-copy-button-to-System-Info-panel-31f6d73d36508148a06ae5f478ba62bf)
by [Unito](https://www.unito.io)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/locales/en/main.json

@@ -93,6 +93,7 @@
     "reportIssueTooltip": "Submit the error report to Comfy Org",
     "reportSent": "Report Submitted",
     "copyToClipboard": "Copy to Clipboard",
+    "copySystemInfo": "Copy System Info",
     "copyAll": "Copy All",
     "openNewIssue": "Open New Issue",
     "showReport": "Show Report",