LuaParser: run Spring.TimeCheck's callback under unitsync/dedicated

[tomjn]

Under UNITSYNC and DEDICATED, TimeCheck compiled to return 0, silently dropping the function it was handed. The shipped gamedata/defs.lua wraps all unitdef/weapondef/etc. loading in Spring.TimeCheck(...), so ProcessUnits() ends up with an empty root and throws root unitdef table invalid — unitsync reports zero units for every game whose defs.lua uses TimeCheck (i.e. the standard springcontent path). Only the profiling timer needs to be excluded from those builds, not the call itself.

Surfaced by a lobby that enumerates units via unitsync; most consumers only read checksums/options, so it went unnoticed.

This also enables the callback under DEDICATED — that seems correct (the function shouldn't discard its argument), but flagging in case that build skips it deliberately.

[sprunk]

Looks alright.

There are other parts of the interface gated under if !DEDI && !UNITSYNC checks you might want to look at, but these would raise questions that are probably best kicked down the road for now.

[tomjn]

Oh there's other stuff but part of it is silly things like reading mod options or map options without checking first if those APIs exist

I've worked around it for now by grabbing unit definitions via lua with shims and polyfills

[sprunk]

That's part of what I'm talking about though. Unitsync should probably define spGetModOptions and just have it return an empty table rather than requiring every game to sprinkle nil checks over their code.