feat!: remove deprecated APIs (#3090)

- Remove CascadeController and @Cascades decorator (use @lit/context)
- Remove SlotController.anonymous (use SlotController.default)
- Remove pf-popover closeButtonLabel / close-label attribute
  (use accessible-close-label)

pfeCustomElementsManifestConfig was already removed from the codebase.

Closes #2975, closes #2974, closes #2973, closes #2972

Assisted-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: bennypowers

.changeset/remove-deprecated-apis.md

@@ -0,0 +1,13 @@
+---
+"@patternfly/pfe-core": major
+"@patternfly/elements": major
+---
+
+Removed deprecated APIs:
+
+- **`CascadeController`** and **`@cascades`** decorator are removed.
+  Use [`@lit/context`](https://lit.dev/docs/data/context/) instead for
+  sharing data between parent and child elements.
+- **`SlotController.anonymous`** is removed. Use `SlotController.default` instead.
+- **`pf-popover`**: the `close-label` attribute and `closeButtonLabel` property
+  are removed. Use `accessible-close-label` instead.

core/pfe-core/controllers/cascade-controller.ts

@@ -7,8 +7,6 @@ import {
 export class SlotController implements SlotControllerPublicAPI {
   public static default = Symbol('default slot') satisfies symbol as symbol;
 
-  /** @deprecated use `default` */
-  public static anonymous: symbol = this.default;
 
   static attribute = 'ssr-hint-has-slotted' as const;
 

core/pfe-core/controllers/slot-controller-server.ts

@@ -130,8 +130,6 @@ class SlotRecord {
 export class SlotController implements SlotControllerPublicAPI {
   public static default = Symbol('default slot') satisfies symbol as symbol;
 
-  /** @deprecated use `default` */
-  public static anonymous: symbol = this.default;
 
   #slotRecords = new Map<string | typeof SlotController.default, SlotRecord>();
 

core/pfe-core/controllers/slot-controller.ts

@@ -1,5 +1,4 @@
 export * from './decorators/bound.js';
-export * from './decorators/cascades.js';
 export * from './decorators/deprecation.js';
 export * from './decorators/initializer.js';
 export * from './decorators/listen.js';

core/pfe-core/decorators.ts

@@ -22,7 +22,6 @@
     "./core.js": "./core.js",
     "./decorators.js": "./decorators.js",
     "./controllers/activedescendant-controller.js": "./controllers/activedescendant-controller.js",
-    "./controllers/cascade-controller.js": "./controllers/cascade-controller.js",
     "./controllers/css-variable-controller.js": "./controllers/css-variable-controller.js",
     "./controllers/floating-dom-controller.js": "./controllers/floating-dom-controller.js",
     "./controllers/internals-controller.js": "./controllers/internals-controller.js",
@@ -41,7 +40,6 @@
     "./controllers/timestamp-controller.js": "./controllers/timestamp-controller.js",
     "./controllers/tabs-controller.js": "./controllers/tabs-controller.js",
     "./decorators/bound.js": "./decorators/bound.js",
-    "./decorators/cascades.js": "./decorators/cascades.js",
     "./decorators/deprecation.js": "./decorators/deprecation.js",
     "./decorators/initializer.js": "./decorators/initializer.js",
     "./decorators/observed.js": "./decorators/observed.js",

core/pfe-core/decorators/cascades.ts

@@ -9,7 +9,7 @@ import { classMap } from 'lit/directives/class-map.js';
 import { ifDefined } from 'lit/directives/if-defined.js';
 import { FloatingDOMController } from '@patternfly/pfe-core/controllers/floating-dom-controller.js';
 import { SlotController } from '@patternfly/pfe-core/controllers/slot-controller.js';
-import { deprecation } from '@patternfly/pfe-core/decorators/deprecation.js';
+
 import { bound } from '@patternfly/pfe-core/decorators/bound.js';
 import { ComposedEvent, StringListConverter } from '@patternfly/pfe-core/core.js';
 
@@ -161,13 +161,6 @@ export class PfPopover extends LitElement {
    */
   @property({ reflect: true, attribute: 'accessible-close-label' }) accessibleCloseLabel?: string;
 
-  /**
-   * @deprecated do not use the color-palette attribute, which was added by mistake. use context-providing containers (e.g. rh-card) instead
-   */
-  @deprecation({
-    alias: 'accessible-close-label',
-    attribute: 'close-label',
-  }) closeButtonLabel?: string;
 
   /**
    * The text announced by the screen reader to indicate the popover's severity.
@@ -268,7 +261,7 @@ export class PfPopover extends LitElement {
             <pf-button id="close-button"
                        part="close-button"
                        plain
-                       label="${this.accessibleCloseLabel ?? this.closeButtonLabel ?? 'Close popover'}"
+                       label="${this.accessibleCloseLabel ?? 'Close popover'}"
                        @click="${this.hide}"
                        @keydown="${this.#onKeydown}"
                        ?hidden="${this.hideClose}">