Implement support for Glint language server v2

[mogstad]

Zed just got support for forwarding tsserver messages in the latest preview. The caveat it only works if the language server is named vue-language-server. I've asked if they are willing to support other language-servers in the same fasion but I haven't heard back.

The implementation is just Vue's language server, but replaced vue's packages with Glint's packages.

This works, but should probably not be released/merged, leaving it here for ref or for people to try if you really want to try Glint v2 and are not using Vue.

    "Glimmer (TypeScript)": {
      "language_servers": ["vtsls", "..."],
      "prettier": {
        "allowed": true,
        "parser": "ember-template-tag",
        "plugins": ["prettier-plugin-ember-template-tag"]
      }
    },
    "Glimmer (JavaScript)": {
      "language_servers": ["vtsls", "..."],
      "prettier": {
        "allowed": true,
        "parser": "ember-template-tag",
        "plugins": ["prettier-plugin-ember-template-tag"]
      }
    },

[billybonks]

I tried with these settings, got the double deceleration, but everything else is throwing errors when it shouldn't be.

    "Glimmer (JavaScript)": {
      "language_servers": ["vtsls", "..."],
      "prettier": {
        "allowed": true,
        "parser": "ember-template-tag",
        "plugins": ["prettier-plugin-ember-template-tag"]
      }
    },

[mogstad]

Just to verify: You've downloaded and built the extension from this branch? And using Glint v2