[Bug]: New emitter options in init template doesn't work well with the config one

[timotheeguerin]

Describe the bug

The config always override the emitters option, I think they should merge in some way.

Reproduction

tsp init https://gist.githubusercontent.com/timotheeguerin/addfb7e137bd41abaf0b80d42ad82e64/raw/5b7f59e12a4c046705e50d4fa7f1e6fef14cbebe/scafold.json

Template

{
  "rest": {
    "title": "Generic REST API",
    "description": "Create a project representing a generic REST API",
    "compilerVersion": "0.64.0",
    "config": {
      "emit": [
        "@typespec/openapi3"
      ]
    },
    "emitters": {
      "@typespec/openapi3": {
        "selected": true,
        "options": {
          "emitter-output-dir": "{output-dir}/schema"
        }
      },
      "@typespec/http-client-csharp": {
        "options": {
          "emitter-output-dir": "{output-dir}/clients/csharp"
        }
      }
    }
  }
}

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• The provided reproduction is a minimal reproducible example of the bug.