lnrpc: add devrpc doc tags to enable lncli api doc generation

lnrpc/devrpc/dev.proto

@@ -6,8 +6,26 @@ package devrpc;
 
 option go_package = "github.com/lightningnetwork/lnd/lnrpc/devrpc";
 
+/*
+ * Comments in this file will be directly parsed into the API
+ * Documentation as descriptions of the associated method, message, or field.
+ * These descriptions should go right above the definition of the object, and
+ * can be in either block or // comment format.
+ *
+ * An RPC method can be matched to an lncli command by placing a line in the
+ * beginning of the description in exactly the following format:
+ * lncli: `methodname`
+ *
+ * Failure to specify the exact name of the command will cause documentation
+ * generation to fail.
+ *
+ * More information on how exactly the gRPC documentation is generated from
+ * this proto file can be found here:
+ * https://github.com/lightninglabs/lightning-api
+ */
+
 service Dev {
-    /*
+    /* lncli: `importgraph`
     ImportGraph imports a ChannelGraph into the graph database. Should only be
     used for development.
     */

lnrpc/devrpc/dev.swagger.json

@@ -18,7 +18,7 @@
   "paths": {
     "/v2/dev/importgraph": {
       "post": {
-        "summary": "ImportGraph imports a ChannelGraph into the graph database. Should only be\nused for development.",
+        "summary": "lncli: `importgraph`\nImportGraph imports a ChannelGraph into the graph database. Should only be\nused for development.",
         "operationId": "Dev_ImportGraph",
         "responses": {
           "200": {

lnrpc/devrpc/dev_grpc.pb.go

@@ -19,6 +19,7 @@ const _ = grpc.SupportPackageIsVersion7
 //
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
 type DevClient interface {
+	// lncli: `importgraph`
 	// ImportGraph imports a ChannelGraph into the graph database. Should only be
 	// used for development.
 	ImportGraph(ctx context.Context, in *lnrpc.ChannelGraph, opts ...grpc.CallOption) (*ImportGraphResponse, error)
@@ -45,6 +46,7 @@ func (c *devClient) ImportGraph(ctx context.Context, in *lnrpc.ChannelGraph, opt
 // All implementations must embed UnimplementedDevServer
 // for forward compatibility
 type DevServer interface {
+	// lncli: `importgraph`
 	// ImportGraph imports a ChannelGraph into the graph database. Should only be
 	// used for development.
 	ImportGraph(context.Context, *lnrpc.ChannelGraph) (*ImportGraphResponse, error)