Design pillar: SSR-safe by construction (no module-top-level window access)

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ahize must import cleanly in any SSR environment (Next.js App Router, Nuxt 3, Remix, SvelteKit, Astro) without touching `window`/`document` at module scope. Every public method is a no-op when non-browser.

Evidence

• `"Document is not defined" error on Next.JS when Implementing the library  crisp-im/crisp-sdk-web#10` — "`document is not defined` on Next.js" "Document is not defined" error on Next.JS when Implementing the library  crisp-im/crisp-sdk-web#10
• `The operand of a 'delete' operator must be optional. crisp-im/crisp-sdk-web#22` — Vercel build fails on `delete window.CRISP_TOKEN_ID` under `--isolatedModules` The operand of a 'delete' operator must be optional. crisp-im/crisp-sdk-web#22
• `Crisp not working on nextJS build on Cloudflare Pages crisp-im/crisp-sdk-web#40` — Crisp dies on Cloudflare Pages deploy Crisp not working on nextJS build on Cloudflare Pages crisp-im/crisp-sdk-web#40
• `NextJS 13 reading properties of undefined devrnt/react-use-intercom#633` — "NextJS 13 reading properties of undefined" NextJS 13 reading properties of undefined devrnt/react-use-intercom#633
• `[react-use-intercom] onHide, onShow, onUserEmailSupplied, boot Intercom instance is not initalized yet (NextJS 15) devrnt/react-use-intercom#726` — "Boot Intercom instance is not initialized yet (NextJS 15)" [react-use-intercom] onHide, onShow, onUserEmailSupplied, boot Intercom instance is not initalized yet (NextJS 15) devrnt/react-use-intercom#726
• `Next.js + App router + [lang] folder devrnt/react-use-intercom#649` — Next.js App Router + `[lang]` folder Next.js + App router + [lang] folder devrnt/react-use-intercom#649
• `window.Intercom undefined when using next.js nhagen/react-intercom#43` — "window.Intercom undefined when using next.js" window.Intercom undefined when using next.js nhagen/react-intercom#43
• `Not working on production build created with create-react-app  nhagen/react-intercom#45` — "Not working on production build" (`null is not an object` on `document.body.appendChild`) Not working on production build created with create-react-app  nhagen/react-intercom#45
• `SyntaxError: Cannot use import statement outside a module tawk/tawk-messenger-react#6` — "SyntaxError: Cannot use import statement outside a module" SyntaxError: Cannot use import statement outside a module tawk/tawk-messenger-react#6
• `The chat widget sometimes appear during dev localhost:3000 but doesn't appear at all when deployed to vercel tawk/tawk-messenger-react#24` — "Chat appears in dev but not in Vercel deploy" The chat widget sometimes appear during dev localhost:3000 but doesn't appear at all when deployed to vercel tawk/tawk-messenger-react#24
• `Bug : Window is not defined with NextJs aaronhayes/react-use-hubspot-form#10` — "Window is not defined with NextJs" Bug : Window is not defined with NextJs aaronhayes/react-use-hubspot-form#10
• `Throws undefined errors when using Gatsby aaronhayes/react-use-hubspot-form#29` — "Throws undefined errors with Gatsby" Throws undefined errors when using Gatsby aaronhayes/react-use-hubspot-form#29
• `canUseDom is a function but is being used as a boolean B3nnyL/react-zendesk#44` — "canUseDom is a function but is being used as a boolean" canUseDom is a function but is being used as a boolean B3nnyL/react-zendesk#44
• `window.zE ist not a function dansmaculotte/vue-zendesk#34`/`zendesk: document exact CSP directives incl. wss://widget-mediator.zopim.com #23`/`Design pillar: identity state machine (HMAC/JWT first-class, no session leaks) #4` — `window.zE is not a function` on SSR window.zE ist not a function dansmaculotte/vue-zendesk#34

Contract

1. No `window`/`document` references at module scope. Always behind `isBrowser()` guard.
2. `delete` only through `Reflect.deleteProperty` on a narrowed reference.
3. Build with `verbatimModuleSyntax: true` + `isolatedModules: true` — already configured.
4. CI matrix must include: Next.js 14 + App Router, Next.js 15, Nuxt 3, Remix, SvelteKit, Astro, Cloudflare Workers.
5. Add `ahize/server` stub entry so SSR bundles never tree-pull any DOM code.

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Implemented in c532a7c