feat: Adding service worker gateway node type and subdomain redirection

[SAHU-01]

Fixes #1336

Description

Adds a new Service Worker Gateway node type to IPFS Companion, enabling trustless, browser-based IPFS content fetching without requiring a local IPFS node.

Implementation

• Added service_worker_gateway as a new node type option
• Redirects IPFS/IPNS requests to configured SW gateway (default: https://inbrowser.link)
• Disables publishing features (upload, pinning, WebUI) when SW Gateway is active
• Added UI for configuring gateway URL with production/staging options

Testing

• Redirect functionality works for IPFS/IPNS paths
• Settings persist across browser restarts
• Publishing features properly disabled
• Node type switching works correctly

Known Limitations

• Service Worker Gateway (inbrowser.link) may have issues some resources may return 501/504 errors from the gateway service itself

Screen Recording

Untitled.design.1.mp4

Reviewer: @lidel

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