tsk-11: Make URLs more dynamic (#15)

Closes #11

Reviewed-on: phoenix/textsender#15

package-lock.json

@@ -8,6 +8,7 @@
       "name": "textsender",
       "version": "0.0.8",
       "dependencies": {
+        "dotenv": "^17.4.2",
         "react": "^19.2.7",
         "react-dom": "^19.2.7",
         "react-router-dom": "^7.18.0"
@@ -1219,6 +1220,18 @@
         "node": ">=8"
       }
     },
+    "node_modules/dotenv": {
+      "version": "17.4.2",
+      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-17.4.2.tgz",
+      "integrity": "sha512-nI4U3TottKAcAD9LLud4Cb7b2QztQMUEfHbvhTH09bqXTxnSie8WnjPALV/WMCrJZ6UV/qHJ6L03OqO3LcdYZw==",
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=12"
+      },
+      "funding": {
+        "url": "https://dotenvx.com"
+      }
+    },
     "node_modules/electron-to-chromium": {
       "version": "1.5.380",
       "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.5.380.tgz",