refactor!: validate arguments with zod instead of ow

[vdusek]

Replaces ow with zod for runtime argument validation, mirroring apify/apify-sdk-js#636 and apify/crawlee#3716 so all three packages share one error type and message format. Input validation only — response validation is a separate PR.

How it works

• ArgumentValidationError and validate() are a hand-synced copy of the @crawlee/core / SDK ones — apify-client sits below both in the dependency graph.
• zod ^4.0.0 matches the merged SDK PR; crawlee's open PR allows ^3 || ^4, so all three dedupe onto one copy.
• The local formatter recurses into invalid_union, so a failed union lists every arm the way ow.any() did, and it replaces zod's self-contradictory expected number, received number / expected date, received Date — both worth upstreaming.
• Schemas use z.strictObject / z.looseObject / z.enum, not the deprecated .strict() / .passthrough() / z.nativeEnum().
• chunkSize now works wherever the options interface extends PaginationOptions, via a shared paginationOptionsShape the schemas spread. It used to type-check but throw; ow's exactShape had the same gap.

Browser bundle

• Tree-shaking and minification are back on in rsbuild.config.ts, off since the webpack-to-rsbuild migration in chore: update eslint, adopt prettier and rsbuild #671. Now 288 kB raw / 87 kB gzip, from 1439 kB / 273 kB — below the 946 kB / 203 kB before this PR. A 320 kB budget fails the build, so it cannot grow unnoticed again.
• Class names stay unmangled: ApifyApiError takes its name from constructor.name, and ResourceClient.waitForFinish() parses the resource name out of it.
• Zod installs its English locale as a module-level side effect but ships "sideEffects": false, so tree-shaking drops it and messages degrade to a bare Invalid input — for anyone bundling apify-client, not just us. The locale is now passed in per parse, which also keeps it out of the zod config shared with the rest of the process. Covered, with the class names, by test/browser_bundle.test.ts.

Breaking changes

• Invalid arguments throw ArgumentValidationError (exported from apify-client), not ow's ArgumentError — different messages, the zod issues on issues, the original ZodError on cause.
• Arrays and functions no longer pass where a plain object is expected: update() / create() fields, TaskClient.start() / call() input, the storage schema option, DatasetClient.pushItems() items.
• Infinity no longer passes on numeric options such as waitSecs, timeoutSecs or memory, and an invalid Date no longer passes on startedBefore / startedAfter — z.number() requires a finite number and z.date() a valid date, where ow only checked the type.
• Options that were declared but always rejected at runtime are gone from the types: chunkSize on downloadItems() and createItemsPublicUrl(), signature on createItemsPublicUrl() and createKeysPublicUrl() — a compile error now instead of a throw.
• Date, Map, Set and other class instances still pass as objects, as under ow.

✍️ Drafted by Claude Code

[github-actions]

⚠️ There are broken links in the documentation.

See more at https://github.com/apify/apify-client-js/actions/runs/31005542533#summary-92304422147

[B4nan]

Follow-ups: the browser bundle grows from 946 kB to 1446 kB raw (203 kB -> 272 kB gzip), because rsbuild.config.ts disables tree-shaking and minification; .strict(), .passthrough() and z.nativeEnum() are deprecated in zod 4 and could move to z.strictObject / z.looseObject / z.enum; chunkSize is missing from every .strict() list schema (pre-existing — ow's exactShape had the same gap).

I would rather fix it here before it gets merged. We don't want to use any deprecated methods, and this PR introduces the bundle size issue.

[vdusek]

I would rather fix it here before it gets merged. We don't want to use any deprecated methods, and this PR introduces the bundle size issue.

OK, I'll check it out

[vdusek]

@B4nan it's ready for a re-check