Add support for jumping without resetting the callstack

[willvale]

Based on similar experimental code in the C# runtime.

I use this for jumping back to the start of the current knot, in order to implement dialogue which can be cancelled and restarted cleanly, so the player doesn't miss out on important information.

E.g.

SIL_VERIFY(m_runner->move_to(m_runner->get_current_knot(), false));

@JBenda is this something you'd be interested in? It needs a bit more work to make it complete, but IMO the idea is useful.

[github-actions]

Ink Proof Results

These results are obtained by running the Ink-Proof Testing Suite on the compiled binaries in this pull request.

System	Results
Linux x64	130/130 passed
MacOSX-ARM	DISABLED
MacOSX	DISABLED
Windows x64	130/130 passed

[JBenda]

I like the idea of "restarting" a convo
but currently do not see which data you want to keep that are not stored in globals anyway.

So if I understand it correctly, the difference between
SIL_VERIFY(m_runner->move_to(m_runner->get_current_knot(), false)); and SIL_VERIFY(m_runner->move_to(m_runner->get_current_knot(), true)); would that threads will stay valid?