feat(webui): platform proxy URL copy & node quick-route creation

[123hi123]

Summary

• Platform proxy URL copy: Added Host:Port + Proxy Token inputs (persisted via localStorage) on the platform list page. Each platform tile now has a link icon button that copies the HTTP forward proxy URL (http://PlatformName:token@host:port) to clipboard.
• Node quick-route creation: Added a button in the node pool actions column to instantly create a dedicated platform that routes exclusively through a single node using an exact regex filter on the node tag.
• Clipboard fallback using document.execCommand("copy") for non-HTTPS contexts.
• Added zh-CN / en-US translation keys for all new UI strings.

Test plan

• Open platform list page, fill in Host:Port and Token inputs, verify localStorage persistence across page refresh
• Click the link icon on a platform tile, verify the correct proxy URL is copied to clipboard
• Open node pool page, click the Layers icon on a node row, verify a new dedicated platform is created with correct regex filter
• Verify the created platform only routes through the target node

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