chore: update signature due to Iterable and Collectable refactoring

src/foreach-yield.md

@@ -46,11 +46,16 @@ The workhorse behind the `foreach-yield` construct is the `Iterable` trait
 (discussed in the previous section) and the `Collectable` trait. 
 
 ```flix
-pub trait Collectable[m: Type -> Type] {
+pub trait Collectable[t: Type] {
+    ///
+    /// The element type of the Collectable.
+    ///
+    type Elm[t]: Type
+
     ///
     /// Run an Iterator collecting the results.
     ///
-    pub def collect(iter: Iterator[a, r]): m[a] \ r with Order[a]
+    pub def collect(iter: Iterator[Collectable.Elm[t], ef, r]): t \ (ef + Collectable.Aef[t] +  r)
 }
 ```
 

src/foreach.md

@@ -79,11 +79,16 @@ defines a single signature:
 ///
 /// A trait for immutable data structures that can be iterated.
 ///
-pub trait Iterable[t: Type -> Type] {
+pub trait Iterable[t] {
+     ///
+    /// The element type of the Iterable.
+    ///
+    type Elm[t]: Type
+
     ///
     /// Returns an iterator over `t`.
     ///
-    pub def iterator(rc: Region[r], t: t[a]): Iterator[a, r, r] \ r
+    pub def iterator(rc: Region[r], t: t): Iterator[Iterable.Elm[t], r + aef, r] \ (r + aef) where Iterable.Aef[t] ~ aef
 }
 ```