chore: migrate to Effect v4

[antonin-morel-spiko]

Summary

Migrates the library, tests and docs to Effect v4 (effect@4.0.0-rc.117), following the effect-v3-to-v4 migration reference.

The example app migration is stacked in #17, to merge after 2.0.0 is published.

Breaking change

v4 removed Runtime.Runtime<R>. The runtime option now accepts a Context.Context<R> or a ManagedRuntime. A major changeset is included.

Library

• Runner dispatch: Context.isContext → Effect.runPromiseExitWith(context), otherwise runtime.runPromiseExit.
• Cancellation: dropped the hand-rolled raceFirst + Effect.async abort race and pass { signal } to the run functions (v4 interrupts the fiber on abort, including an already-aborted signal).
• Cause.isInterruptedOnly → Cause.hasInterruptsOnly.
• Peer dependency: effect@^4.0.0-rc.117.

Tests / docs

• Context.Tag → Context.Service, Layer.toRuntime → Layer.build, Schema.Record(key, value).

[Copilot]

Copilot review overview

🟡 Changes recommended

The example lockfile is stale relative to its manifest, and documentation still contains removed v3 runtime references.

Review effort: Lite
Findings: 1 · 1

Open (2)

• Regenerate example lockfile for migrated v4 dependencies · New
• Update docs still referencing removed v3 Runtime API · New

What changed in this PR

Migrates the library, tests, documentation, and example application from Effect v3 to v4.

Changes:

• Replaces runtime APIs with Context/ManagedRuntime.
• Updates cancellation and error handling.
• Migrates example HTTP APIs and dependencies.
• Adds a major-release changeset.

File	Description
test/​useInfiniteEffectSuspenseQuery.test.ts	Updates infinite suspense query tests for Effect v4.
test/​useInfiniteEffectQuery.test.ts	Updates infinite query tests for Effect v4.
test/​useEffectSuspenseQuery.test.ts	Updates suspense query tests.
test/​useEffectSuspenseQueries.test.ts	Updates suspense batch query tests.
test/​useEffectQuery.test.ts	Updates query tests.
test/​useEffectQueries.test.ts	Updates multi-query tests.
test/​useEffectMutation.test.ts	Updates mutation tests.
test/​toQueryOptions.test.ts	Migrates query option test fixtures.
test/​infiniteEffectQueryOptions.test.ts	Migrates infinite query option tests.
test/​effectQueryOptions.test.ts	Migrates query option tests.
src/​useInfiniteEffectSuspenseQuery.ts	Updates infinite suspense runtime types.
src/​useInfiniteEffectQuery.ts	Updates infinite query runtime types.
src/​useEffectSuspenseQuery.ts	Updates suspense query runtime types.
src/​useEffectSuspenseQueries.ts	Updates suspense batch runtime types.
src/​useEffectQuery.ts	Updates query runtime types.
src/​useEffectQueries.ts	Updates multi-query runtime types.
src/​useEffectMutation.ts	Migrates mutation runtime handling.
src/​types.ts	Updates public runtime option types.
src/​internal/​createEffectQueryFn.ts	Updates runtime execution and cancellation.
pnpm-lock.yaml	Locks Effect v4 dependencies.
package.json	Updates the Effect peer dependency.
example/​src/​client.ts	Migrates HTTP client imports.
example/​src/​backend.ts	Migrates server setup.
example/​src/​App.tsx	Updates v4 error handling.
example/​src/​api.ts	Migrates HTTP API definitions.
example/​package.json	Updates example dependencies.
docs/​index.md	Updates dependency-injection documentation.
bun.lock	Updates dependency metadata.
.changeset/​effect-v4.md	Adds the major-release changeset.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

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[antonin-morel-spiko]

Upgrade to stable version in #18 instead of release candidate