Make caps.{Capability, Classifier, Shareable, Control} non-experimental

These are all neccessary for boundary.Label

Author: natsukagami

compiler/src/dotty/tools/dotc/core/Definitions.scala

@@ -2109,10 +2109,9 @@ class Definitions {
    */
   @tu lazy val ccExperimental: Set[Symbol] = Set(
     CapsModule, CapsModule.moduleClass, PureClass,
-    Caps_Capability, // TODO: Remove when Capability is stabilized
     RequiresCapabilityAnnot,
     captureRoot, Caps_CapSet, Caps_ContainsTrait, Caps_ContainsModule, Caps_ContainsModule.moduleClass, UseAnnot,
-    Caps_Mutable, Caps_Sharable, Caps_Control, Caps_Classifier, ConsumeAnnot,
+    Caps_Mutable/* , Caps_Sharable, Caps_Control, Caps_Classifier -- already stable*/, ConsumeAnnot,
     CapsUnsafeModule, CapsUnsafeModule.moduleClass,
     CapsInternalModule, CapsInternalModule.moduleClass,
     RetainsAnnot, RetainsCapAnnot, RetainsByNameAnnot)

library/src/scala/caps/package.scala

@@ -22,14 +22,12 @@ import annotation.{experimental, compileTimeOnly, retainsCap}
  * But even without capture checking, extending this trait can be useful for documenting the intended purpose
  * of a class.
  */
-@experimental
 trait Capability extends Any
 
 /** A marker trait for classifier capabilities that can appear in `.only`
  *  qualifiers. Capability classes directly extending `Classifier` are treated
  *  as classifier capbilities
  */
-@experimental
 trait Classifier
 
 /** The universal capture reference. */
@@ -43,13 +41,11 @@ trait Mutable extends Capability, Classifier
 /** Marker trait for capabilities that can be safely shared in a concurrent context.
   * During separation checking, shared capabilities are not taken into account.
   */
-@experimental
 trait Sharable extends Capability, Classifier
 
 /** Base trait for capabilities that capture some continuation or return point in
  *  the stack. Examples are exceptions, labels, Async, CanThrow.
  */
-@experimental
 trait Control extends Sharable, Classifier
 
 /** Carrier trait for capture set type parameters */

tests/run-tasty-inspector/stdlibExperimentalDefinitions.scala

@@ -32,15 +32,11 @@ val experimentalDefinitionInLibrary = Set(
   "scala.annotation.retainsCap",
   "scala.Pure",
   "scala.caps.CapSet",
-  "scala.caps.Capability",
-  "scala.caps.Classifier",
   "scala.caps.Contains",
   "scala.caps.Contains$",
   "scala.caps.Contains$.containsImpl",
   "scala.caps.Exists",
   "scala.caps.Mutable",
-  "scala.caps.Sharable",
-  "scala.caps.Control",
   "scala.caps.consume",
   "scala.caps.internal",
   "scala.caps.internal$",