fix(core)!: deprecate cascades decorator

[bennypowers]

Lit context provides us with an easier to manage and more robust alternative to the imperative cascades system, let's migrate to that and remove this in PFE 4

What I did

1. mark @cascades and CascadeController as deprecated

Notes to reviewers:

RHDS uses @cascades in one file:

❯ rg cascades
elements/rh-tabs/rh-tabs.ts
8:import { cascades, deprecation } from '@patternfly/pfe-core/decorators.js';
140:  @cascades('rh-tab')
150:  @cascades('rh-tab', 'rh-tab-panel')
156:  @cascades('rh-tab', 'rh-tab-panel')

which we will remove when we update to TabsController, following PFE 3 release

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: f6ebd9f0c174217cd17c5cd70d1de8897ce18e3e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

| Name | Type | | -------------------- | ----- | | @patternfly/pfe-core | Major | | @patternfly/elements | Patch |

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[bennypowers]

@Arathy-s does cp elements use this?

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