A folder with no signer name or key verifies Markdown and saves it unsigned (#8)

Co-authored-by: Danny Kim <temeddix@gmail.com>
Co-committed-by: Danny Kim <temeddix@gmail.com>

manifest.json

@@ -2,7 +2,7 @@
   "schemaVersion": 1,
   "id": "memona/signature",
   "name": "Signature",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "apiVersion": "0.1.0",
   "description": "Open a WebDAV server as a folder, and sign the Markdown saved to it with an ENS name.",
   "license": "MIT",
@@ -37,16 +37,16 @@
         {
           "key": "ensName",
           "label": "Signer name",
-          "description": "The ENS name that signs saved Markdown, for example laptop.alice.eth",
+          "description": "The ENS name that signs saved Markdown, for example laptop.alice.eth. Leave it and the key empty to only verify",
           "kind": "text",
-          "required": true
+          "required": false
         },
         {
           "key": "privateKey",
           "label": "Signing key",
-          "description": "The private key of the address that owns this name",
+          "description": "The private key of the address that owns this name. Leave it and the name empty to only verify",
           "kind": "password",
-          "required": true
+          "required": false
         },
         {
           "key": "rpcUrl",