feat(prisma): derive schemas from a datamodel

[tada5hi]

Stacked on #838. Two features: schema derivation from a datamodel, and client-bound adapter construction.

Bind the adapter from a model delegate

const adapter = new PrismaAdapter({ model: prisma.user });

One argument. The model name, the datamodel (relations, cardinality, nullability, column types) and the active provider are read off the client the delegate belongs to, through its runtime backref. { client: prisma, model: 'User' } works with a plain name, provider/metadata remain overridable, and the fully explicit { provider, metadata } form stays as the private-API-free path.

Honesty note: the reads use private but long-stable client internals (_runtimeDataModel, _activeProvider, the delegate $name/$parent markers; Prisma has no public reflection API, prisma/orm#19392). Guarded accordingly:

• every read fails typed instead of guessing (unresolvable client, unreadable provider),
• pruned edge/wasm runtime datamodels (no cardinality/nullability) are rejected typed with the hand-written datamodel as the documented escape hatch,
• the engine suite pins the shapes against a real generated client: the delegate-bound adapter must produce byte-identical arguments to the datamodel-bound one and select the same records through the engine, and the shapes are verified to survive $extends.

Schema derivation

const registry = defineSchemaRegistryWithDatamodel(prisma, {
    schemas: {
        user: {
            fields: { allowed: 'inherit' },       // the model's field names
            filters: { allowed: ['id', 'name'] }, // authorization stays yours
        },
    },
});

Mirrors @rapiq/typeorm's entity derivation contract: derivation supplies shape (schema name, relation allow-list, schemaMapping), authorization stays explicit, hand-written schemas take precedence, and name collisions or unmatched option keys fail loudly. assertSchemaMatchesModel turns schema/model drift into a boot-time SchemaModelMismatchError carrying every offending key. All entry points accept a client instance, a runtime datamodel or a DMMF datamodel.

Testing

33 new specs (client resolution, derivation, assert) plus engine-backed checks against the real generated client on SQLite and PostgreSQL. Acceptance test runs a derived registry through the full pipeline: wire input -> URL codec (relation traversal via derived schemaMapping) -> adapter -> args object.

Notes

• change-case added as a dependency (same as @rapiq/typeorm, for the derived names).
• Docs lead with the delegate-bound form; the explicit form is documented as the stable path with the private-API caveat spelled out.
• Still deferred: scalar-list operators, _count ordering.

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