Schema: Add schema's for detailed fundchannel methods

doc/schemas/fundchannel_cancel.request.json

@@ -0,0 +1,14 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "id"
+  ],
+  "properties": {
+    "id": {
+      "type": "pubkey",
+      "description": "the node id of the remote peer with which to cancel"
+    }
+  }
+}

doc/schemas/fundchannel_complete.request.json

@@ -0,0 +1,19 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "id",
+    "psbt"
+  ],
+  "properties": {
+    "id": {
+      "type": "pubkey",
+      "description": "id is the node id of the remote peer."
+    },
+    "psbt": {
+      "type": "string",
+      "description": "the transaction to use for funding (does not need to be signed but must be otherwise complete)"
+    }
+  }
+}

doc/schemas/fundchannel_start.request.json

@@ -8,28 +8,36 @@
   ],
   "properties": {
     "id": {
-      "type": "pubkey"
+      "type": "pubkey",
+      "description": "id is the peer id obtained from connect."
     },
     "amount": {
-      "type": "msat"
+      "type": "msat_or_all",
+      "description": "The amount that the channel will be funded."
     },
     "feerate": {
-      "type": "feerate"
+      "type": "feerate",
+      "description": "Sets the feerate for the subsequent commitment transaction."
     },
     "announce": {
-      "type": "boolean"
+      "type": "boolean",
+      "description": "Whether or not to announce the channel."
     },
     "close_to": {
-      "type": "hex"
+      "type": "string",
+      "description": "A bitcoin address to which the channel funds should be sent to on close."
     },
     "push_msat": {
-      "type": "msat"
+      "type": "msat",
+      "description": "The amount of millisatoshis to push to the channel at open. This is a gift to the peer."
     },
     "mindepth": {
-      "type": "u32"
+      "type": "u32",
+      "description": "Number of confirmations required before we consider the channel active"
     },
     "reserve": {
-      "type": "msat"
+      "type": "msat",
+      "description": "The amount we want the peer to maintain on its side"
     },
     "channel_type": {
       "type": "array",