README: slide-mounted not petri-dish

Croissant: use RAI/1.0/ namespace; switch petri-dish to slide-mounted

Restore required RAI fields (biases, use cases, social impact, collection, source) per NeurIPS 2026 D&B spec

Croissant: add missing @context terms (jsonPath, column, etc.) + datePublished

Simplify croissant.json (drop verbose RAI/prov fields)

Add parquet shards (phoebi6 + phoebi4) for HF dataset viewer

Add parquet shards for HF dataset viewer (phoebi6 + phoebi4 configs)

Remove internal hosting plan from public release

Initial PHOEBI release: PHOEBI-6 (40 combos, 6 species) + PHOEBI-4 (14 combos, 4 species)

initial commit