Split syntax module to reduce compilation time (#1852)

Hello,
Splitting `Swarm.Language.Syntax` into submodules reduces the compilation time quite a bit. Currently, it takes the most of time out of all the modules. Here's a chart:

![CleanShot 2024-05-17 at 17 09 38@2x](https://github.com/swarm-game/swarm/assets/15181803/fc2672ea-4032-4140-93e7-16d9d4aaea69)

That's ~20s for simplifier (with overall compilation time of 4.3 mins)

Just taking out the types and functions related to `Constants` and putting them in a separate module results in:

![CleanShot 2024-05-17 at 17 11 45@2x](https://github.com/swarm-game/swarm/assets/15181803/ac4c57e9-af46-4861-b305-8540c1b01bab)

Thats ~8.5 seconds for simplifier (with overall compilation time of 3.9 mins)

Just for added info, timings taken on a 2019 macbook with i7 processor (6 core and 32 GB RAM)

Changes include:
- `Swarm.Language.Syntax` split into the following modules:
  - `Swarm.Language.Syntax.Comments` - Types for working with comments.
  - `Swarm.Language.Syntax.Type` - Core types (`Syntax'`, `Term'` and `DelayType`)
  - `Swarm.Language.Syntax.Pattern` - Pattern synonyms for untyped terms
  - `Swarm.Language.Syntax.Loc` -  Types for working with location in source code (`SrcLoc` and related types)
  - `Swarm.Language.Syntax.Util` - Helper functions (Eg: `mkTuple`, `freeVarsS` etc)

Compilation chart after the split:

![CleanShot 2024-05-18 at 15 20 17@2x](https://github.com/swarm-game/swarm/assets/15181803/b6a138dd-c0a3-416f-a620-2d82cb418c7d)

`Swarm.Language.Syntax` is no longer the most time taking module.

Closes #1844

src/swarm-engine/Swarm/Game/Scenario/Topography/Navigation/Util.hs

@@ -9,7 +9,7 @@ import Linear (V2)
 import Swarm.Game.Location
 import Swarm.Game.Robot
 import Swarm.Game.Universe (Cosmic, planar)
-import Swarm.Language.Direction
+import Swarm.Language.Syntax.Direction
 
 -- |
 -- Computes the relative offset vector between a 'Robot' and a 'Location'

src/swarm-engine/Swarm/Game/Step/Util/Inspect.hs

@@ -15,7 +15,7 @@ import Swarm.Game.Robot
 import Swarm.Game.State
 import Swarm.Game.State.Robot
 import Swarm.Game.Universe
-import Swarm.Language.Direction
+import Swarm.Language.Syntax.Direction
 import Swarm.Util (listEnums)
 
 -- * World queries

src/swarm-engine/Swarm/Game/Value.hs

@@ -16,7 +16,7 @@ import Swarm.Game.Entity
 import Swarm.Game.Location
 import Swarm.Game.Robot
 import Swarm.Game.Scenario.Topography.Area (AreaDimensions (..))
-import Swarm.Language.Direction
+import Swarm.Language.Syntax.Direction
 import Swarm.Language.Value
 
 -- * Patterns