Add textobject queries for protobuf grammar.

Given `message Foo {string s = 1;}`
- `mat` selects `message Foo {string s = 1}`
- `mit` selects `{string s = 1;}`

Given `service SearchService { rpc Search(Req) returns (Resp); }
- `mit` or `mat` selects `Req` or `Resp`
- `mif` or `maf` selects `rpc Search(Req) returns (Resp);`
- `mit` selects { rpc Search(Req) returns (Resp); }`
- `mat` selects `service SearchService { rpc Search(Req) returns (Resp); }`

runtime/queries/protobuf/textobjects.scm

@@ -0,0 +1,10 @@
+(message (messageBody) @class.inside) @class.around
+(enum (enumBody) @class.inside) @class.around
+(service (serviceBody) @class.inside) @class.around
+
+(rpc (enumMessageType) @parameter.inside) @function.inside
+(rpc (enumMessageType) @parameter.around) @function.around
+
+(comment) @comment.inside
+(comment)+ @comment.around
+