Rename base package to pf everywhere, to match tutorial

compiler/parse/src/header.rs

@@ -204,7 +204,7 @@ pub enum ImportsEntry<'a> {
         Collection<'a, Loc<ExposesEntry<'a, &'a str>>>,
     ),
 
-    /// e.g. `base.Task` or `base.Task.{ after }` or `base.{ Task.{ Task, after } }`
+    /// e.g. `pf.Task` or `pf.Task.{ after }` or `pf.{ Task.{ Task, after } }`
     Package(
         &'a str,
         ModuleName<'a>,

compiler/parse/src/module.rs

@@ -786,7 +786,7 @@ fn imports_entry<'a>() -> impl Parser<'a, ImportsEntry<'a>, EImports> {
     map_with_arena!(
         and!(
             and!(
-                // e.g. `base.`
+                // e.g. `pf.`
                 maybe!(skip_second!(
                     shortname(),
                     word1(b'.', EImports::ShorthandDot)