1## ADDED Requirements23### Requirement: Pack previews SHALL expose nonfatal rule warnings without serializing them4Local CommonJS previews and data-only shared-link previews SHALL apply the same supported-feature and property validation. A successful preview SHALL return a bounded `warnings` collection separate from `errors: []`, with `word`, `levelId`, `levelTitle`, optional `sentence`, a player-language `message`, and technical `detail`. Warnings SHALL not prevent installation and SHALL not be serialized into exported CommonJS source, shared payloads, installed pack data, or engine snapshots. Unknown required features SHALL fail atomically before installation.56#### Scenario: Local and shared preview agree on warnings7- **WHEN** the same valid pack with an initially formed unknown predicate is previewed from a local module and a shared link8- **THEN** both previews succeed and expose the same warning context without installing the pack910#### Scenario: Diagnostics stay outside portable data11- **WHEN** a warned pack is exported as CommonJS or encoded into a share URL and decoded again12- **THEN** the authored data remains valid, the warning is recomputed on preview, and no transient diagnostic field appears in the exported data1314#### Scenario: Unsupported shared feature fails before Gift installation15- **WHEN** a shared payload declares a feature unsupported by the current host16- **THEN** the decoder returns a player-readable error and Gift cannot install partial content