Restore Monaco find widget in Dag Code view

[choo121600]

Cmd/Ctrl+F in the Dag Code view opened the browser's native find bar instead of Monaco's find widget, and the widget icons rendered incorrectly in DEV_MODE=true.

Root cause

• configureMonaco.ts imported only editor.api, which does not include
  the standalone find contribution or codicon font styles.
• In DEV_MODE, Vite served font assets from :5173 while the page was
  served from :28080, causing font requests to resolve incorrectly and
  return HTML instead of TTF files.

Fix

• Explicitly import findController and codiconStyles in
  configureMonaco.ts.
• Set server.origin = "http://localhost:5173" in vite.config.ts so
  Vite emits correct asset URLs for cross-origin development setups.

Before

After

part of: #67359

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opus 4.7

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