Return all matching pads from the search route

[Copilot]

The plugin’s search endpoint was only returning the last matching pad, even though it scans all pads. This change makes the route return the full set of matches and avoids scanning when the query is empty.

• Search behavior

  • Replace the single-result object with an array of matching pad IDs.
  • Preserve case-insensitive matching across pad text.
  • Return JSON directly from the route.

• Empty query handling

  • Short-circuit empty searches with [] instead of walking every pad.

• Regression coverage

  • Add route-level coverage for:
    • multiple matching pads returned together
    • empty queries skipping the pad scan

const searchString = (req.query.query || '').toLowerCase();
const result = [];

if (!searchString) return res.json(result);

if (padText.toLowerCase().indexOf(searchString) !== -1) {
  result.push(pad);
}

res.json(result);