Fix some of the scaladoc links (#295)

* Fix some of the scaladoc links

If ones removes the line `Compile / doc / sources := Nil,` from the
build and run `sbt doc` one get warnings like:
```
[warn] -- Warning: modules/deriving/src/main/scala/shapeless3/deriving/kinds.scala:66:7
[warn] 66 |  type Kind[M <: Mirror, O <: Up] = (M of O) { type Kind = self.type }
[warn]    |       ^
[warn]    |       Couldn't resolve a member for the given link query: Mirror
```
Based on the dicussion in scala/scala3#20028
my understanding is that this means that scaldoc can not resolve the
existing link.

The reason I want to fix this is that it will also show up for users
implementing custom `Kinds`. E.g in some private project where I extends
Kind I get warnings like this in my scaladoc:
```
[warn] -- Warning: modules/deriving/src/main/scala/shapeless3/deriving/kinds.scala:66:7
[warn] Couldn't resolve a member for the given link query: Mirror
```
(the error changed slighlty in the latest Scala 3 version). Since I
don't think this is solvable for a user I suggest that we just make the
links absolute which seems to solve the warnings.

* No longer exclude all sources from scaladoc

* Fix shapeless.Annotations links

Author: eejbyfeldt

build.sbt

@@ -141,7 +141,6 @@ lazy val commonSettings = Seq(
   scalacOptions ++= Seq("-Werror", "-Yexplicit-nulls", "-deprecation"),
   Test / scalacOptions += "-Xmax-inlines:256",
   Test / scalacOptions -= "-Yexplicit-nulls",
-  Compile / doc / sources := Nil,
   libraryDependencies += "com.github.sbt" % "junit-interface" % "0.13.3" % "test",
   testOptions += Tests.Argument(TestFrameworks.JUnit, "-a", "-s", "-v")
 )

modules/deriving/src/main/scala/shapeless3/deriving/annotation.scala

@@ -153,7 +153,7 @@ object Annotations:
  *
  * }}}
  *
- * This implementation is based on [[shapeless.Annotations]] by Alexandre Archambault.
+ * This implementation is based on `shapeless.Annotations` by Alexandre Archambault.
  *
  * @tparam A:
  *   type annotation type
@@ -211,7 +211,7 @@ object TypeAnnotations:
  *
  * }}}
  *
- * This implementation is based on [[shapeless.Annotations]] by Alexandre Archambault.
+ * This implementation is based on `shapeless.Annotations` by Alexandre Archambault.
  *
  * @tparam T:
  *   product or sum type, whose fields or constructors are annotated
@@ -267,7 +267,7 @@ object AllAnnotations:
  *
  * }}}
  *
- * This implementation is based on [[shapeless.Annotations]] by Alexandre Archambault.
+ * This implementation is based on `shapeless.Annotations` by Alexandre Archambault.
  *
  * @tparam T:
  *   product or sum type, whose fields or constructors are annotated

modules/deriving/src/main/scala/shapeless3/deriving/kinds.scala

@@ -55,29 +55,29 @@ import scala.deriving.*
 trait Kind[Up <: AnyKind, Tup <: AnyKind, Mono[_ <: Up], Head[_ <: Tup] <: Up, Tail[_ <: Tup] <: Tup]:
   self =>
 
-  /** Similar to [[Mirror.Of]] but generalized to this kind. */
+  /** Similar to [[scala.deriving.Mirror.Of]] but generalized to this kind. */
   infix type of[M <: Mirror, O <: Up] = M {
     type MirroredType = O
     type MirroredMonoType = Mono[O]
     type MirroredElemTypes <: Tup
   }
 
-  /** A [[Mirror]] for types of this kind, including the given scope of the enclosing object. */
+  /** A [[scala.deriving.Mirror]] for types of this kind, including the given scope of the enclosing object. */
   type Kind[M <: Mirror, O <: Up] = (M of O) { type Kind = self.type }
 
-  /** A [[Mirror]] for types of this kind. */
+  /** A [[scala.deriving.Mirror]] for types of this kind. */
   type Generic[O <: Up] = Kind[Mirror, O]
 
-  /** A [[Mirror.Product]] for types of this kind. */
+  /** A [[scala.deriving.Mirror.Product]] for types of this kind. */
   type ProductGeneric[O <: Up] = Kind[Mirror.Product, O]
 
-  /** A [[Mirror.Sum]] for types of this kind. */
+  /** A [[scala.deriving.Mirror.Sum]] for types of this kind. */
   type CoproductGeneric[O <: Up] = Kind[Mirror.Sum, O]
 
   object Generic:
 
     /**
-     * Attaches the given scope of the enclosing object to a given [[Mirror]] as a type refinement.
+     * Attaches the given scope of the enclosing object to a given [[scala.deriving.Mirror]] as a type refinement.
      *
      * The Scala compiler can automatically add type refinements to synthesized mirrors, but not to given mirrors in the
      * current scope or to user-defined mirrors. The scope of the enclosing object is necessary to resolve extension
@@ -126,16 +126,16 @@ trait Kind[Up <: AnyKind, Tup <: AnyKind, Mono[_ <: Up], Head[_ <: Tup] <: Up, T
     case _ *: _ => F[Head[T]] *: LiftP[F, Tail[T]]
     case _ => EmptyTuple
 
-  /** Given a [[Mirror]], provides instances of the type class `F` for all fields or variants of `T`. */
+  /** Given a [[scala.deriving.Mirror]], provides instances of the type class `F` for all fields or variants of `T`. */
   inline given mkInstances[F[_ <: Up], T <: Up](using gen: Mirror of T): Instances[F, T] = inline gen match
     case given (Mirror.Product of T) => mkProductInstances[F, T]
     case given (Mirror.Sum of T) => mkCoproductInstances[F, T]
 
-  /** Given a [[Mirror.Product]], provides instances of the type class `F` for all fields of `T`. */
+  /** Given a [[scala.deriving.Mirror.Product]], provides instances of the type class `F` for all fields of `T`. */
   inline given mkProductInstances[F[_ <: Up], T <: Up](using gen: Mirror.Product of T): ProductInstances[F, T] =
     ErasedProductInstances[self.type, F[T], LiftP[F, gen.MirroredElemTypes]](gen)
 
-  /** Given a [[Mirror.Sum]], provides instances of the type class `F` for all variants of `T`. */
+  /** Given a [[scala.deriving.Mirror.Sum]], provides instances of the type class `F` for all variants of `T`. */
   inline given mkCoproductInstances[F[_ <: Up], T <: Up](using gen: Mirror.Sum of T): CoproductInstances[F, T] =
     ErasedCoproductInstances[self.type, F[T], LiftP[F, gen.MirroredElemTypes]](gen)