Convert `cell.isSymbol` to use a LUT

[qwerasd205]

Follow-on to #8510

This lives in renderer/cell.zig when really it should be in font, but that's a refactor for another day. Right now we just need to do this TODO since it's in a hot path and is way too much work with all these checks in a row when it could be a LUT.

ghostty/src/renderer/cell.zig

Lines 251 to 261 in 3ac2da9

	pub fn isSymbol(cp: u21) bool {
	// TODO: This should probably become a codegen'd LUT
	return ziglyph.general_category.isPrivateUse(cp) or
	ziglyph.blocks.isDingbats(cp) or
	ziglyph.blocks.isEmoticons(cp) or
	ziglyph.blocks.isMiscellaneousSymbols(cp) or
	ziglyph.blocks.isEnclosedAlphanumerics(cp) or
	ziglyph.blocks.isEnclosedAlphanumericSupplement(cp) or
	ziglyph.blocks.isMiscellaneousSymbolsAndPictographs(cp) or
	ziglyph.blocks.isTransportAndMapSymbols(cp);
	}

This should probably use the existing unicode LUT generation stuff we have, though it's for a boolean property so maybe worth trimming down, idk. Should validate this change with benchmarks to make sure the overhead of the LUT isn't worse than the multiple lookups here.

[mitchellh]

I'm going to throw this into the 1.2 milestone just to try and see if it makes sense.