Drop backward compatibility with versions earlier than 1.7.2

[SebastianMC]

For now the plugin code contains a series of backward compatible conditional sections, which make the code complex and less readable in some places.

The goal of this ticket:

• bump up the npm dependency on Obsidian (API) to 1.7.2
• bump up the required Obsidian to 1.7.2
• remove the support for core Starred plugin - it was superseded by the Bookmarks
• remove the two areas of code which handle the integration with legacy Obsidian sorting

Also take the opportunity to upgrade TS and other libraries and tools