fix: preserve jscpd reports above project threshold

[liorp]

Problem

The jscpd adapter inherits a repository's .jscpd.json threshold. When
duplication exceeds that threshold, jscpd writes a valid JSON report and exits

1. Desloppify currently treats that as an execution failure and discards the
   report, so scans warn that duplication detection was skipped.

Minimal reproduction:

1. Configure jscpd with "threshold": 0.
2. Scan a project containing a duplicate block.
3. Observe that jscpd writes jscpd-report.json but desloppify reports
   jscpd exited with errors and imports no clusters.

Fix

Run jscpd with --threshold 100. Desloppify consumes the report itself, so a
project-level CI threshold must not prevent the adapter from reading valid
results.

Verification

• Added a regression test that failed before the threshold override.
• 14 passed for the jscpd adapter tests.
• 6823 passed, 17 skipped for the full test suite with full extras installed.
• Verified against a real TypeScript monorepo: the warning disappeared and
  duplication clusters were imported.