🧹 [code health improvement] Augment Window type to replace 'window as any' castings

[kuasar-mknd]

🎯 What: The global Window interface was extended in src/env.d.ts to include strongly-typed custom properties used across multiple components. This allowed the complete removal of unsafe window as any type assertions and // eslint-disable-next-line @typescript-eslint/no-explicit-any comments throughout the codebase.

💡 Why: Relying on explicit any casting bypasses the TypeScript compiler, leaving the code vulnerable to typos and type mismatches. Defining the custom properties directly on the global Window interface improves type safety, developer experience (through IDE autocompletion), and overall maintainability.

✅ Verification: Verified by compiling the application (pnpm run build), running the TypeScript compiler (pnpm run typecheck), linting (pnpm run lint), and successfully running the e2e Playwright test suite.

✨ Result: A safer, cleaner, and strictly typed codebase with 0 eslint-disable workarounds regarding window accesses.

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PR created automatically by Jules for task 11506260394677494612 started by @kuasar-mknd

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