Fix Stream.mapAccumArrayEffect data-first usage

[fubhy]

Fixes the data-first overload dispatch for Stream.mapAccumArrayEffect, which returned a curried function instead of a Stream.

Adds a focused regression test and patch changeset.

Validation:

• targeted Stream regression test
• pnpm lint-fix
• git diff --check

The worktree-local root typecheck could not resolve workspace packages through its temporary dependency symlink; the same integrated source previously passed the root pnpm check.

[changeset-bot]

🦋 Changeset detected

Latest commit: 8842d0a

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 30 packages

Name	Type
effect	Patch
@effect/opentelemetry	Patch
@effect/platform-browser	Patch
@effect/platform-bun	Patch
@effect/platform-deno	Patch
@effect/platform-node-shared	Patch
@effect/platform-node	Patch
@effect/vitest	Patch
@effect/ai-anthropic	Patch
@effect/ai-openai-compat	Patch
@effect/ai-openai	Patch
@effect/ai-openrouter	Patch
@effect/atom-react	Patch
@effect/atom-solid	Patch
@effect/atom-vue	Patch
@effect/sql-clickhouse	Patch
@effect/sql-d1	Patch
@effect/sql-libsql	Patch
@effect/sql-mssql	Patch
@effect/sql-mysql2	Patch
@effect/sql-pg	Patch
@effect/sql-pglite	Patch
@effect/sql-sqlite-bun	Patch
@effect/sql-sqlite-do	Patch
@effect/sql-sqlite-node	Patch
@effect/sql-sqlite-react-native	Patch
@effect/sql-sqlite-wasm	Patch
@effect/docgen	Patch
@effect/doctest	Patch
@effect/openapi-generator	Patch

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[pullfrog]

✅ No new issues found.

Reviewed changes — a one-character fix to mapAccumArrayEffect's dual predicate, a focused regression test, and a patch changeset.

• dual predicate fix: isStream(args) → isStream(args[0]) at packages/effect/src/Stream.ts:7442. All 19 other dual calls in this file already use isStream(args[0]); this was the lone outlier.
• Regression test: data-first Stream.mapAccumArrayEffect(stream, initial, f) → .pipe(Stream.runCollect) with exact output assertion.
• Changeset: patch-level.

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[github-actions]

Bundle Size Analysis

Generated from PR build output; treat the content below as untrusted.

File Name	Current Size	Previous Size	Difference
basic.ts	6.63 KB	6.63 KB	0.00 KB (0.00%)
batching.ts	9.42 KB	9.42 KB	0.00 KB (0.00%)
brand.ts	6.31 KB	6.31 KB	0.00 KB (0.00%)
cache.ts	10.16 KB	10.16 KB	0.00 KB (0.00%)
config.ts	20.04 KB	20.04 KB	0.00 KB (0.00%)
differ.ts	19.93 KB	19.93 KB	0.00 KB (0.00%)
http-client.ts	21.02 KB	21.02 KB	0.00 KB (0.00%)
logger.ts	10.32 KB	10.32 KB	0.00 KB (0.00%)
metric.ts	8.55 KB	8.55 KB	0.00 KB (0.00%)
optic.ts	7.33 KB	7.33 KB	0.00 KB (0.00%)
pubsub.ts	14.46 KB	14.46 KB	0.00 KB (0.00%)
queue.ts	11.13 KB	11.13 KB	0.00 KB (0.00%)
schedule.ts	10.31 KB	10.31 KB	0.00 KB (0.00%)
schema-class.ts	18.86 KB	18.86 KB	0.00 KB (0.00%)
schema-fromJsonSchemaDocument.ts	28.67 KB	28.67 KB	0.00 KB (0.00%)
schema-representation-roundtrip.ts	24.99 KB	24.99 KB	0.00 KB (0.00%)
schema-string-transformation.ts	12.99 KB	12.99 KB	0.00 KB (0.00%)
schema-string.ts	10.65 KB	10.65 KB	0.00 KB (0.00%)
schema-template-literal.ts	14.85 KB	14.85 KB	0.00 KB (0.00%)
schema-toArbitraryLazy.ts	21.66 KB	21.66 KB	0.00 KB (0.00%)
schema-toCodeDocument.ts	24.08 KB	24.08 KB	0.00 KB (0.00%)
schema-toCodecJson.ts	18.91 KB	18.91 KB	0.00 KB (0.00%)
schema-toEquivalence.ts	18.73 KB	18.73 KB	0.00 KB (0.00%)
schema-toFormatter.ts	18.59 KB	18.59 KB	0.00 KB (0.00%)
schema-toJsonSchemaDocument.ts	22.33 KB	22.33 KB	0.00 KB (0.00%)
schema-toRepresentation.ts	19.25 KB	19.25 KB	0.00 KB (0.00%)
schema.ts	18.12 KB	18.12 KB	0.00 KB (0.00%)
stm.ts	12.11 KB	12.11 KB	0.00 KB (0.00%)
stream.ts	9.37 KB	9.37 KB	0.00 KB (0.00%)