tml-2912: PSL native scalar lists (author, migrate, infer end-to-end) (#870)

## tml-2912 — PSL native scalar lists (slice 2 of native-scalar-arrays)

Flips the implicit gate slice 1 built behind: a user can now author SQL
scalar lists in PSL (`tags String[]`) and get them **end to end** —
native Postgres array columns (`text[]`), element-wise codec round-trip,
authoring diagnostics, capability gating, and the headline `posts.tags
String[]` milestone checkpoint (project AC1).

Stacked on slice 1 (#846, merged). The load-bearing change is one line
in the interpreter — replacing the JSONB fallback with the element
descriptor + `many: true`; the rest is making the authoring layer
correct about lists.

### Dispatches
- **D1** — interpreter flip: PSL scalar lists lower to native array
storage columns (the JSONB fallback turned out to live in **3**
coordinated sites, all removed).
- **D1b** — make `StorageColumnTypes`/`StorageColumnInputTypes`
`many`-aware (the insert/select builders consume the storage maps; only
the domain maps were wrapped before).
- **D2** — reject incoherent list constructs (execution default / `@id`
/ `autoincrement` on a list) with actionable diagnostics.
- **D3** — authoring-time capability gating: a list field against a
target whose adapter doesn't report `scalarList` (SQLite) is rejected;
threads a merged `CapabilityMatrix` to the interpreter via the existing
`mergeCapabilityMatrices`.
- **D4** — element-non-null `CHECK (array_position(col, NULL) IS NULL)`
(enforce-on-all) + array-typed `@default([])`/`@default([...])`
validation; rejects a scalar default on a list.
- **D5** — end-to-end milestone (AC1 author→migrate→infer round-trip) +
element fidelity (`DateTime[]`/`Bytes[]`/`Decimal[]`) + Mongo parity
(NFR4).

### Acceptance criteria
AC1 (milestone round-trip), AC6 (FR3 diagnostics), AC8 PSL-half
(non-null-element CHECK), AC9 (array defaults), AC10 (capability
gating), AC2/NFR1 (element fidelity), NFR4 (Mongo parity), NFR2 (no
scalar regression — `fixtures:check` byte-clean). **9/9 PASS.**

### Notes for reviewers
- **Element nullability is enforce-on-all.** PSL has no `T?[]`
(element-nullable) syntax, so every PSL-authored list column carries the
non-null-element CHECK; no `elementNullable` IR flag was needed.
- **CHECK is emitted as DDL, not via ADR-156.** ADR-156 check
constraints are value-set/`IN(...)`-only and can't express
`array_position(...)`, so D4 added a small `CheckExpressionConstraint`
DDL node (`<table>_<col>_elem_not_null`).
- **Known limitation (carried to slice 3):** opt-in `--strict` verify
would false-flag the element-non-null CHECK as drift, because
introspection doesn't parse it back. Default verify is non-strict and
unaffected; the AC1 infer round-trip is clean (`text[]` → `String[]`).

🤖 Generated with [Claude Code](https://claude.com/claude-code)


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added support for scalar list fields across authoring, schema
generation, migrations, and contract emission.
* Scalar lists now use native array storage where supported, with
updated typing and round-trip behavior.
* Improved check-constraint handling to support both value-set and
expression-based validations.

* **Bug Fixes**
* Fixed list default parsing, including quoted values and special
characters.
* Improved validation for unsupported list features and stricter schema
verification for array fields.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Signed-off-by: Serhii Tatarintsev <tatarintsev@prisma.io>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: SevInf

apps/telemetry-backend/src/prisma/contract.d.ts

@@ -6,7 +6,7 @@ model TelemetryEvent {
   installationId String
   version        String
   command        String
-  flags          String[]
+  flags          Json
   runtimeName    String
   runtimeVersion String
   os             String
@@ -15,7 +15,7 @@ model TelemetryEvent {
   databaseTarget String?
   tsVersion      String?
   agent          String?
-  extensions     String[]
+  extensions     Json
 
   @@index([ingestedAt])
   @@map("telemetry_event")

apps/telemetry-backend/src/prisma/contract.json

@@ -162,10 +162,8 @@ describe('telemetry POST /events', () => {
     const row = await fetchSingleRow();
     expect(row.installationId).toBe(maxString);
     expect(row.command).toBe(maxString);
-    expect(row.flags).toHaveLength(64);
-    expect(row.flags[0]).toBe(maxArrayItem);
-    expect(row.extensions).toHaveLength(64);
-    expect(row.extensions[0]).toBe(maxArrayItem);
+    expect(row.flags).toEqual(manyArrayItems);
+    expect(row.extensions).toEqual(manyArrayItems);
   });
 
   it('rejects strings beyond the configured schema bounds with 400', async () => {

apps/telemetry-backend/src/prisma/contract.prisma

@@ -1,5 +1,6 @@
 import type { Contract } from '@prisma-next/contract/types';
 import type { CodecLookup } from '@prisma-next/framework-components/codec';
+import type { CapabilityMatrix } from '@prisma-next/framework-components/components';
 import type {
   AssembledAuthoringContributions,
   ControlMutationDefaults,
@@ -45,6 +46,7 @@ export interface ContractSourceContext {
   readonly codecLookup: CodecLookup;
   readonly controlMutationDefaults: ControlMutationDefaults;
   readonly resolvedInputs: readonly string[];
+  readonly capabilities: CapabilityMatrix;
 }
 
 /** Lets format-aware tooling avoid file-extension sniffing and opaque loader introspection. */

apps/telemetry-backend/test/handler.test.ts

@@ -1,5 +1,7 @@
 import type { JsonValue } from '@prisma-next/contract/types';
 import { blindCast } from '@prisma-next/utils/casts';
+import type { CapabilityMatrix } from '../shared/capabilities';
+import { mergeCapabilityMatrices } from '../shared/capabilities';
 import type { Codec } from '../shared/codec';
 import type { AnyCodecDescriptor } from '../shared/codec-descriptor';
 import type { CodecLookup, CodecMeta, CodecRef, CodecRegistry } from '../shared/codec-types';
@@ -62,6 +64,7 @@ export interface ControlStack<
   readonly authoringContributions: AssembledAuthoringContributions;
   readonly scalarTypeDescriptors: ReadonlyMap<string, string>;
   readonly controlMutationDefaults: ControlMutationDefaults;
+  readonly capabilities: CapabilityMatrix;
 }
 
 export interface CreateControlStackInput<
@@ -522,5 +525,10 @@ export function createControlStack<TFamilyId extends string, TTargetId extends s
     authoringContributions: assembleAuthoringContributions(allDescriptors),
     scalarTypeDescriptors,
     controlMutationDefaults: assembleControlMutationDefaults(allDescriptors),
+    capabilities: mergeCapabilityMatrices({}, [
+      target,
+      ...(adapter ? [adapter] : []),
+      ...orderedExtensionPacks,
+    ]),
   };
 }

packages/1-framework/1-core/config/src/contract-source-types.ts

@@ -1,3 +1,4 @@
+export type { CapabilityMatrix } from '../shared/capabilities';
 export { mergeCapabilityMatrices } from '../shared/capabilities';
 export type {
   AdapterDescriptor,

packages/1-framework/1-core/framework-components/src/control/control-stack.ts

@@ -9,7 +9,7 @@
 
 import { blindCast } from '@prisma-next/utils/casts';
 
-type CapabilityMatrix = Record<string, Record<string, boolean>>;
+export type CapabilityMatrix = Record<string, Record<string, boolean>>;
 
 function isPlainObject(value: unknown): value is Record<string, unknown> {
   return typeof value === 'object' && value !== null && !Array.isArray(value);

packages/1-framework/1-core/framework-components/src/exports/components.ts

@@ -15,6 +15,7 @@ export interface ResolvedAttributeArg {
   readonly kind: 'positional' | 'named';
   readonly name?: string;
   readonly value: string;
+  readonly expression?: ExpressionAst;
   readonly span: PslSpan;
 }
 
@@ -69,10 +70,12 @@ function readResolvedArgList(
   const args: ResolvedAttributeArg[] = [];
   for (const arg of argList.args()) {
     const name = arg.name()?.name();
+    const expression = arg.value();
     args.push({
       kind: name !== undefined ? 'named' : 'positional',
       ...(name !== undefined ? { name } : {}),
-      value: renderExpression(arg.value()),
+      value: renderExpression(expression),
+      ...(expression !== undefined ? { expression } : {}),
       span: nodePslSpan(arg.syntax, sourceFile),
     });
   }

packages/1-framework/1-core/framework-components/src/shared/capabilities.ts

@@ -631,6 +631,7 @@ class ControlClientImpl implements ControlClient {
         codecLookup: stack.codecLookup,
         controlMutationDefaults: stack.controlMutationDefaults,
         resolvedInputs: contractConfig.source.inputs ?? [],
+        capabilities: stack.capabilities,
       };
       const providerResult = await contractConfig.source.load(sourceContext);
       if (!providerResult.ok) {