docs: deprecate textarea type for input component

[DitwanP]

Related Issue: #9974

Summary

Deprecate the "textarea" value for the type property on the input component.

[geospatialem]

Using the @deprecated tag would deprecate the entire property. Maybe we should consider adding the language that its deprecated in the JSDoc without using the tag? Perhaps similar to shell-panel's displayMode prop for "float"?

Also, for consistency we should use calcite-text-area to specify the component, similar to how calcite-action-bar is referenced in the displayMode prop as well:

calcite-design-system/packages/calcite-components/src/components/shell-panel/shell-panel.tsx

Lines 166 to 179 in 4e5bf1d

	/**
	* Specifies the display mode of the component, where:
	*
	* `"dock"` displays at full height adjacent to center content,
	*
	* `"overlay"` displays at full height on top of center content, and
	*
	* `"float"` [Deprecated] does not display at full height with content separately detached from `calcite-action-bar` on top of center content.
	*
	* `"float-content"` does not display at full height with content separately detached from `calcite-action-bar` on top of center content.
	*
	* `"float-all"` detaches the `calcite-panel` and `calcite-action-bar` on top of center content.
	*/
	@property({ reflect: true }) displayMode: DisplayMode = "dock";

[geospatialem]

Small consideration, otherwise LGTM! 🚀📝