Simplify codebase and fix Enter key on home page

- Enter key now triggers createGame action on home page
- Remove redundant setNickname action from home page
- Remove unused code: join channel, Leave(), Stop() methods
- Consolidate ID generation into game.GenerateID()
- Remove unused CreatedAt field from Game struct

go.mod

@@ -2,16 +2,12 @@ module github.com/ryanhamamura/c4
 
 go 1.25.4
 
-require (
-	github.com/go-via/via-plugin-picocss v0.1.1
-	github.com/ryanhamamura/via v0.2.3
-)
+require github.com/ryanhamamura/via v0.2.3
 
 require (
 	github.com/CAFxX/httpcompression v0.0.9 // indirect
 	github.com/alexedwards/scs/v2 v2.9.0 // indirect
 	github.com/andybalholm/brotli v1.2.0 // indirect
-	github.com/go-via/via v0.1.4 // indirect
 	github.com/klauspost/compress v1.18.0 // indirect
 	github.com/starfederation/datastar-go v1.0.3 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect