Add new license purple-computer-sal-1.1 for the Purple Computer Source-Available License 1.1

[MGpromax]

Fixes #5248

Adds purple-computer-sal-1.1 for the Purple Computer Source-Available License 1.1 (personal, private use only), text from the homepage URL in the issue. Key and category: Source-available follow the existing *-sal-* entries; owner: Purple Computer per the copyright line.

Detection before this change: the text matched unknown-license-reference AND mit, which badly misrepresents a license that reserves all redistribution and commercial rights. It now detects as purple-computer-sal-1.1 with score 100.

Validation (same for all six license additions from this batch):

• scancode-reindex-licenses runs clean
• self-detection and ignorables validation tests pass (--test-suite=validate tests/licensedcode/test_detection_validate.py), with ignorables generated by the test regen tooling rather than by hand
• pytest tests/licensedcode/test_license_models.py passes locally

Tasks

• Reviewed contribution guidelines
• PR is descriptively titled 📑 and links the original issue above 🔗
• Tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR
• Commits are in uniquely-named feature branch and has no merge conflicts 📁
• Updated documentation pages (if applicable) -- not applicable
• Updated CHANGELOG.rst (if applicable) -- not applicable