Refactor solidity highlights.scm

- Use more specific/appropriate captures; change invalid captures
- Don't highlight punctuations in type names (e.g., the brackets in
  'bytes32[]')

tests/query/highlights/solidity/test.sol

@@ -5,6 +5,10 @@
 pragma solidity >=0.7.0 <0.9.0;
 // ^ keyword
 //     ^ tag
+
+import * as something from "anotherFile";
+// ^     ^            ^ include
+
 /// @title Voting with delegation.
 //  ^ attribute
 contract Ballot {
@@ -170,4 +174,9 @@ contract Ballot {
     }
 }
 
+contract Another {
+  Ballot b = new Ballot(new bytes32[](1));
+//           ^ keyword.operator
+}
+
 // vim:ft=solidity