Add "direction" JS field to Structure objects (#3508)

Adds a "direction" field to JS structure objects, which represents the direction the structure is facing (from 0 to 3, in 90 degree increments).

doc/js-objects.md

@@ -25,6 +25,7 @@ In addition, the following properties are defined:
 * ```status``` The completeness status of the structure. It will be one of ```BEING_BUILT``` and ```BUILT```.
 * ```type``` The type will always be ```STRUCTURE```.
 * ```cost``` What it would cost to build this structure. (3.2+ only)
+* ```direction``` The direction the structure is facing. (4.5+ only)
 * ```stattype``` The stattype defines the type of structure. It will be one of ```HQ```, ```FACTORY```, ```POWER_GEN```,
 ```RESOURCE_EXTRACTOR```, ```LASSAT```, ```DEFENSE```, ```WALL```, ```RESEARCH_LAB```, ```REPAIR_FACILITY```,
 ```CYBORG_FACTORY```, ```VTOL_FACTORY```, ```REARM_PAD```, ```SAT_UPLINK```, ```GATE``` and ```COMMAND_CONTROL```.

src/quickjs_backend.cpp

@@ -794,6 +794,7 @@ JSValue convResearch(const RESEARCH *psResearch, JSContext *ctx, int player)
 //;; * ```status``` The completeness status of the structure. It will be one of ```BEING_BUILT``` and ```BUILT```.
 //;; * ```type``` The type will always be ```STRUCTURE```.
 //;; * ```cost``` What it would cost to build this structure. (3.2+ only)
+//;; * ```direction``` The direction the structure is facing. (4.5+ only)
 //;; * ```stattype``` The stattype defines the type of structure. It will be one of ```HQ```, ```FACTORY```, ```POWER_GEN```,
 //;; ```RESOURCE_EXTRACTOR```, ```LASSAT```, ```DEFENSE```, ```WALL```, ```RESEARCH_LAB```, ```REPAIR_FACILITY```,
 //;; ```CYBORG_FACTORY```, ```VTOL_FACTORY```, ```REARM_PAD```, ```SAT_UPLINK```, ```GATE```, ```STRUCT_GENERIC```, and ```COMMAND_CONTROL```.
@@ -835,6 +836,7 @@ JSValue convStructure(const STRUCTURE *psStruct, JSContext *ctx)
 	QuickJS_DefinePropertyValue(ctx, value, "status", JS_NewInt32(ctx, (int)psStruct->status), JS_PROP_ENUMERABLE);
 	QuickJS_DefinePropertyValue(ctx, value, "health", JS_NewInt32(ctx, 100 * psStruct->body / MAX(1, psStruct->structureBody())), JS_PROP_ENUMERABLE);
 	QuickJS_DefinePropertyValue(ctx, value, "cost", JS_NewInt32(ctx, psStruct->pStructureType->powerToBuild), JS_PROP_ENUMERABLE);
+	QuickJS_DefinePropertyValue(ctx, value, "direction", JS_NewInt32(ctx, UNDEG(psStruct->rot.direction)), JS_PROP_ENUMERABLE);
 	int stattype = 0;
 	switch (psStruct->pStructureType->type) // don't bleed our source insanities into the scripting world
 	{