Polish UI for the inspector

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Goals

• Offer good overview / glance value of what's happening over the protocol
  • Params should be collapsed
• Offer easy search / filtering
  • Partial text match for filtering. For example, typing comp should single out all the completion request / responses
  • Be able to filter by language features, for example
    • completion / completion resolve
    • code lens / code lens resolve
    • formatting / range formatting / on type formatting

Technical

• This should be a web app that's possible to run stand-alone or in VS Code Webview
• This inspector should take two kinds of input
  1. A complete JSON log, which the LanguageClient should write to the output channel if [language-server-id].trace.server is set to json. This allows copy-pasting of a complete log into the visualizer.
  2. JSON Stream. This allows an external data source to send JSON logs continuously to the Inspector, which transforms the JSON event into a visualized DOM element and append to the end.

/cc @dbaeumer

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The most up-to-date UI is hosted at http://lsp-inspector.surge.sh/

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This issue was moved to microsoft/language-server-protocol-inspector#3