Add YAML config system (types and io)

package-lock.json

@@ -26,7 +26,8 @@
         "qrcode-terminal": "^0.12.0",
         "telegram-markdown-v2": "^0.0.4",
         "tsx": "^4.21.0",
-        "typescript": "^5.9.3"
+        "typescript": "^5.9.3",
+        "yaml": "^2.8.2"
       },
       "bin": {
         "lettabot": "dist/cli.js",
@@ -6384,6 +6385,21 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/yaml": {
+      "version": "2.8.2",
+      "resolved": "https://registry.npmjs.org/yaml/-/yaml-2.8.2.tgz",
+      "integrity": "sha512-mplynKqc1C2hTVYxd0PU2xQAc22TI1vShAYGksCCfxbn/dFwnHTNi1bvYsBTkhdUNtGIf5xNOg938rrSSYvS9A==",
+      "license": "ISC",
+      "bin": {
+        "yaml": "bin.mjs"
+      },
+      "engines": {
+        "node": ">= 14.6"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/eemeli"
+      }
+    },
     "node_modules/yauzl": {
       "version": "2.10.0",
       "resolved": "https://registry.npmjs.org/yauzl/-/yauzl-2.10.0.tgz",