fix(formatter): stringify bigint values in JSON diagnostics

[xianjianlf2]

Fixes #4662

Summary

• stringify BigInt values with an n suffix in Formatter.formatJson instead of letting JSON.stringify throw
• add regression coverage for both formatJson and Inspectable.toStringUnknown
• add a patch changeset for the runtime behavior change

Tests

• pnpm test packages/effect/test/Formatter.test.ts
• pnpm lint-fix
• pnpm check

Summary by CodeRabbit

• Bug Fixes
  • Improved JSON diagnostics formatting to safely handle BigInt values without errors.
  • BigInt values are now displayed as strings with an n suffix, including when nested in arrays.
  • Updated formatting documentation to clarify BigInt serialization and indentation behavior.

[changeset-bot]

🦋 Changeset detected

Latest commit: 376aad8

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

This PR includes changesets to release 27 packages

Name	Type
effect	Patch
@effect/opentelemetry	Patch
@effect/platform-browser	Patch
@effect/platform-bun	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/openapi-generator	Patch

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

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Run ID: bcbc9394-ce37-41e3-80fb-d41fd7dbba41

📥 Commits

Reviewing files that changed from the base of the PR and between 4e0be58 and 376aad8.

📒 Files selected for processing (3)

• .changeset/brown-glasses-thank.md
• packages/effect/src/Formatter.ts
• packages/effect/test/Formatter.test.ts

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📝 Walkthrough

Walkthrough

formatJson now safely serializes BigInt values as strings with an n suffix. Documentation, regression tests for formatter and inspectable output, and a patch changeset were added.

Changes

BigInt JSON formatting

Layer / File(s)	Summary
Safe BigInt serialization and regression coverage packages/effect/src/Formatter.ts, packages/effect/test/Formatter.test.ts, .changeset/brown-glasses-thank.md	formatJson converts redacted BigInt values to suffixed strings, documents the behavior, and tests formatter and Inspectable.toStringUnknown output.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested labels: bug

Suggested reviewers: gcanti

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	The BigInt serialization fix and regression tests address the logging failure caused by JSON.stringify in Inspectable output.
Out of Scope Changes check	✅ Passed	All changes support the BigInt serialization fix, test coverage, or release metadata, with no unrelated code changes.

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