feat(fsharp): m01-m06 util, model, rules, random, spawn, game, view with Expecto tests

Co-Authored-By: Claude Opus 5.5 <[email protected]>

fsharp/solutions/Util.fs

@@ -1,2 +1,12 @@
-/// Placeholder; replaced by the m01 utilities.
+/// m01 util: small helpers used by every later module.
+/// (The JavaScript track also writes `pipe` and `compose` here; F# has them built in as `|>` and `>>`.)
 module Snake.Util
+
+let range (n: int) : int list = [ 0 .. n - 1 ]
+
+let dropLast (xs: 'a list) : 'a list =
+    match xs with
+    | [] -> []
+    | _ -> List.take (List.length xs - 1) xs
+
+let contains (xs: 'a list) (p: 'a) (eq: 'a -> 'a -> bool) : bool = List.exists (fun x -> eq x p) xs