test: port export.test.ts + privacy.test.ts → Idris2 (4/4 files; estate port 6/11 complete)

[hyperpolymath]

Completes the partial port from #55 — ubicity now has all 4 TS test files mirrored in Idris2 (18 tests total, 0 failed locally).

What's new

• ExportTest.idr — 5/5 PASS (CSV / GeoJSON struct / DOT graph / Markdown / CSV escaping). All pure string formatting; no SUT bindings required. The Markdown test substitutes the ISO timestamp for the TS toLocaleDateString() because the TS test never asserts on the date format itself.

• PrivacyTest.idr — 5/6 PASS (1 deferred for crypto)

  • Location fuzzing (Double rounding)
  • PII removal — substring find/replace rather than regex; preserves the TS invariants (verifies the email/phone tokens are gone + replacements present)
  • Privacy-level enforcement (Private | Anonymous | Public sum type)
  • Data minimization (record projection)
  • Shareable-dataset filter
  • Deferred: SHA-256 learner-ID anonymization — same constraint as the two CoreTest deferred cases. Idris2 base lacks crypto.

• Main.idr — aggregates all 4 suites

• ubicity-tests.ipkg — registers ExportTest + PrivacyTest

Local run (Idris2 0.8.0, Chez codegen)

```
=== CoreTest === 3 passed, 0 failed
=== MapperTest === 5 passed, 0 failed
=== ExportTest === 5 passed, 0 failed
=== PrivacyTest === 5 passed, 0 failed
=== Total: 18 passed, 0 failed ===
```

Estate-rollout impact

ubicity moves from "partial — 1 of 4 TS files" → "ports complete — all 4 TS files mirrored, 3 sub-cases deferred for crypto". Each deferred case is documented inline in its module with the precise constraint (crypto / JSON parse).

Process note

Originally drafted on top of feat/port-core-tests-to-idris2 (PR #55) before that merged. After #55 squash-landed I cherry-picked just the new commit onto a fresh branch off main — avoids the GitHub stacked-PR orphan trap documented in the auto-memory.