feat: add auto-generated Zod schemas via Hey API plugin

[MathurAditya724]

Add auto-generated Zod v3 schemas from the OpenAPI spec using Hey API's built-in Zod plugin. The schemas are exported from a separate @sentry/api/zod subpath entry point so existing consumers are completely unaffected — only those who opt in by importing from @sentry/api/zod will pull in the zod dependency.

Both the CLI (getsentry/cli) and MCP server (getsentry/sentry-mcp) currently maintain hand-written Zod schemas for Sentry API responses. This change enables them to migrate to auto-generated schemas that stay in sync with the OpenAPI spec automatically.

Usage

import { zAlertRule, zOrganization } from "@sentry/api/zod";

const parsed = zOrganization.parse(rawData);

What changed

• build.mjs: Enable the zod plugin with compatibilityVersion: 3 (Zod v3 syntax, matching both consumer repos). Default plugins (@hey-api/typescript, @hey-api/sdk) are listed explicitly since adding plugins overrides defaults.
• build.mjs: Create src/zod.ts entry point and bundle it to dist/zod.js with zod externalized (not bundled — consumers provide their own zod).
• package.json: Add ./zod subpath export, zod as optional peer dependency, and zod as dev dependency for build-time resolution.

Testing

bun run build && bun run typecheck && bun test — all 28 tests pass, typecheck clean, npm pack produces valid package.

[MathurAditya724]

All 5 CI checks passed (Build, Secret Scan, dependency-review, semgrep, warden). Self-review found no issues — the diff is minimal (3 files, 52 insertions), output verified to use correct Zod v3 syntax with zod externalized from the bundle. Marked ready for review.