chore: adds tests

package.json

@@ -6,19 +6,23 @@
         "build": "node esbuild.config.mjs",
         "push": "npm run build && ts-node publish.ts",
         "format": "prettier --check --ignore-path .gitignore .",
-        "format:fix": "prettier --write --ignore-path .gitignore ."
+        "format:fix": "prettier --write --ignore-path .gitignore .",
+        "test": "jest"
     },
     "dependencies": {
         "@trivago/prettier-plugin-sort-imports": "^6.0.2",
         "@types/screeps": "^3.3.8",
         "dotenv": "^17.4.2",
         "esbuild": "^0.28.0",
+        "jest": "^30.3.0",
         "prettier": "^3.8.3",
+        "ts-jest": "^29.4.9",
         "ts-node": "^10.9.2",
         "typescript": "^6.0.3",
         "zod": "^4.3.6"
     },
     "devDependencies": {
+        "@types/jest": "^30.0.0",
         "@types/node": "^25.6.0"
     },
     "prettier": {
@@ -36,5 +40,24 @@
             "jsx",
             "decorators-legacy"
         ]
+    },
+    "jest": {
+        "testEnvironment": "node",
+        "transform": {
+            "^.+\\.(ts|tsx)$": "ts-jest"
+        },
+        "moduleNameMapper": {
+            "\\.(png|jpg|jpeg|gif|webp|svg|ico)$": "<rootDir>/tests/setup/__mocks__/fileMock.js",
+            "^@/(.*)$": "<rootDir>/src/$1",
+            "^~/(.*)$": "<rootDir>/$1"
+        },
+        "moduleFileExtensions": [
+            "ts",
+            "tsx",
+            "js"
+        ],
+        "testMatch": [
+            "**/?(*.)+(spec|test).[jt]s?(x)"
+        ]
     }
 }