Fix and expand ApiRoute example code

[adamdicarlo0]

Removed Server.Request.map4 and Server.Request.rawBody (which no longer exist), and added multiple path parameters to illustrate how they're used.

"Ignore whitespace" will better highlight what's actually changed.

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🔨 Latest commit	174589e585444be57e8136ff9045ef0013914b95

[adamdicarlo0]

I was trying to use the example code to see what api-routes.json would look like, and ran into Server.Response.map* not existing. Since I reworked it and added a couple of path params for my own purposes, I figured I'd contribute this back.

[dillonkearns]

Thanks!