Remove push subscriptions from local storage and rely upon reticulum handshake to indicate if currently subscribed

This reverts commit 7d257c35.

This reverts commit 5c7e8673, reversing
changes made to 0814f7a1.

Only use the amount of memory needed in sharedbuffergeometry based on networked-drawing configuration. Only create a sharedbuffergeometry object when a pen is first spawned.
Also, reduce the amount of memory used by primitive entities (cursor, spawned pens, teleport-controls)