feat(CdkMenu/CdkContextMenuTriggerFor): Allow CdkMenu to be programmatically opened/closed

## Feature Description

### Current Behaviour

The directive `CdkMenu` is used with combination of `CdkContextMenuTriggerFor`. When user right-clicks (context-menu event), the menu gets opened and clicking on outside of the menu will close the menu.

### New Feature Requested

It would be great if user can manually/programmatically open/close the menu. And also disable closing the menu clicking outside.

#### Possible Solutions

1. Add a boolean input property `cdkContextMenuDisableCloseOnOutsideClick` - This will disable closing the `CdkMenu` on outside click
2. Add an event emitter property `cdkContextMenuTriggered` - This will emit everytime user right-clicks (context-menu event) with the coordinates
3. Add an event emitter property `cdkContextMenuClickedOutside` - This will emit everytime user clicks outside of the `CdkMenu`

### Use Case

This will allow users to handle animations with `CdkMenu` if they want to apply on open/close.

Start by reading the CdkMenu and CdkContextMenuTriggerFor directive entry points and tracing the existing context-menu opening and outside-click closing behavior. Clarify the public API and event semantics for programmatic open/close, disabling outside-click closure, and context-menu/outside-click notifications. Done means the agreed behavior is implemented and covered by the relevant menu tests.

Written by the indexing model from the issue text.