Rewrite no_implicit_prelude to move to a specific rule

This rewrites the intro to be a little more general, and moves the
description of the behavior to a specific rule that can be cited.

Author: ehuss

src/names/preludes.md

@@ -143,7 +143,7 @@ r[names.preludes.no_implicit_prelude]
 ## The `no_implicit_prelude` attribute
 
 r[names.preludes.no_implicit_prelude.intro]
-The *`no_implicit_prelude` [attribute]* may be applied at the crate level or on a module to indicate that it should not automatically bring the [standard library prelude], [extern prelude], or [tool prelude] into scope for that module or any of its descendants.
+The *`no_implicit_prelude` [attribute]* is used to prevent implicit preludes from being brought into scope.
 
 > [!EXAMPLE]
 > ```rust
@@ -172,6 +172,9 @@ Duplicate instances of the `no_implicit_prelude` attribute have no effect.
 > [!NOTE]
 > `rustc` currently warns on subsequent duplicate `no_implicit_prelude` attributes.
 
+r[names.preludes.no_implicit_prelude.excluded-preludes]
+The `no_implicit_prelude` attribute prevents the [standard library prelude], [extern prelude], and the [tool prelude] from being brought into scope for the module or any of its descendants.
+
 r[names.preludes.no_implicit_prelude.lang]
 This attribute does not affect the [language prelude].