Add Writing Desk storage and menu foundation

src/main/resources/data/rivencraft/loot_table/blocks/writing_desk.json

@@ -0,0 +1,4 @@
+{
+  "type": "minecraft:block",
+  "pools": [{ "rolls": 1, "entries": [{ "type": "minecraft:item", "name": "rivencraft:writing_desk" }] }]
+}

src/main/resources/data/rivencraft/recipe/writing_desk.json

@@ -0,0 +1,11 @@
+{
+  "type": "minecraft:crafting_shaped",
+  "category": "misc",
+  "pattern": ["V F", "PPP", "P P"],
+  "key": {
+    "V": { "item": "minecraft:glass_bottle" },
+    "F": { "item": "minecraft:feather" },
+    "P": { "tag": "minecraft:planks" }
+  },
+  "result": { "id": "rivencraft:writing_desk", "count": 1 }
+}