fix: rename podcast name to podcast handle to clarify field usage

- podcast name was too vague and didn't come clearly for users: handle is more relevant
- update
package.json dependencies and remove unnused packages

closes #126

.devcontainer/devcontainer.json

@@ -12,6 +12,7 @@
   "settings": {
     "terminal.integrated.defaultProfile.linux": "bash",
     "editor.formatOnSave": true,
+    "editor.defaultFormatter": "esbenp.prettier-vscode",
     "[php]": {
       "editor.defaultFormatter": "bmewburn.vscode-intelephense-client",
       "editor.formatOnSave": false