Add PWA assets, offline page, and service worker with app-launch overlay

[Bytewave-coder]

Motivation

• Improve installability and offline reliability by adding a web app manifest, service worker, and an offline fallback page.
• Provide brand assets and social preview imagery for sharing and better first impressions.
• Surface a short launch experience to reassure users while the app initializes.

Description

• Added three SVG assets: assets/logo.svg, assets/offline-illustration.svg, and assets/og-image.svg for branding, offline UI, and social previews.
• Enhanced index.html with PWA/meta tags (OG/Twitter), manifest.json and icon links, a preload for the logo, a small app-launch overlay UI (markup + styles + Lottie animation), and scripts to hide the overlay after load and register the service worker plus beforeinstallprompt handling.
• Updated manifest.json with description, id, scope, display_override, icons, categories, lang, and a shortcuts entry to enable installability and better platform integration.
• Added offline.html as a user-friendly offline landing page and overhauled service-worker.js to CACHE_NAME = "naman-ai-cache-v3", include an app shell list, support install/activate lifecycle with cache cleanup, handle message for SKIP_WAITING, use a navigation-aware fetch strategy with offline fallback, and cache successful GET responses.

Testing

• No automated tests were added or run for this change.

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Codex Task

[Bytewave-coder]

Nice

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Remove unconditional suppression of install prompt

Calling event.preventDefault() on every beforeinstallprompt suppresses the browser’s native install UI, and this change does not add any follow-up prompt() call (the event is only stored on window.deferredInstallPrompt). In practice, users never see an install prompt, which is a functional regression for PWA installability unless a custom install button flow is implemented.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Restrict cache-first behavior to static GET assets

This returns cached data before network for every GET request (cachedResponse || networkFetch), so dynamic endpoints are served stale values. The app performs live GET lookups (for example, fetchWikipedia and fetchNews), and with this handler those responses can lag by at least one request and persist stale data when offline. The cache-first branch should be limited to versioned static assets, with network-first/no-cache for live API calls.

Useful? React with 👍 / 👎.