Add EsLint

.eslintrc.json

@@ -0,0 +1,53 @@
+{
+    "env": {
+        "browser": true,
+        "es2021": true
+    },
+    "extends": [
+        "eslint:recommended",
+        "plugin:@typescript-eslint/recommended",
+        "plugin:astro/recommended",
+        "plugin:svelte/recommended"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": "latest",
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "overrides": [
+        {
+            "files": ["*.astro"],
+            "parser": "astro-eslint-parser",
+            "parserOptions": {
+                "sourceType": "module"
+            },
+            "rules": {
+                "astro/no-conflict-set-directives": "error",
+                "astro/no-unused-define-vars-in-style": "error"
+            }
+        }
+    ],
+    "rules": {
+        "comma-spacing": ["error", { "before": false, "after": true }],
+        "no-multiple-empty-lines": ["error", { "max": 1, "maxEOF": 1 }],
+        "indent": [
+            "error",
+            4
+        ],
+        "linebreak-style": [
+            "error",
+            "unix"
+        ],
+        "quotes": [
+            "error",
+            "double"
+        ],
+        "semi": [
+            "error",
+            "always"
+        ]
+    }
+}