Prefer explicit construction to coercion in record initialization

While we support initializing records via coercion from an expression
list, e.g.,

    local x: X = [$x1=1, $x2=2];

this can sometimes obscure the code to readers, e.g., when assigning to
value declared and typed elsewhere. The language runtime has a similar
overhead since instead of just constructing a known type it needs to
check at runtime that the coercion from the expression list is valid;
this can be slower than just writing the readible code in the first
place, see #4559.

With this patch we use explicit construction, e.g.,

    local x = X($x1=1, $x2=2);

scripts/policy/frameworks/intel/seen/http-url.zeek

@@ -5,8 +5,8 @@
 event http_message_done(c: connection, is_orig: bool, stat: http_message_stat) &group="Intel::URL"
 	{
 	if ( is_orig && c?$http )
-		Intel::seen([$indicator=HTTP::build_url(c$http),
-		             $indicator_type=Intel::URL,
-		             $conn=c,
-		             $where=HTTP::IN_URL]);
+		Intel::seen(Intel::Seen($indicator=HTTP::build_url(c$http),
+		                        $indicator_type=Intel::URL,
+		                        $conn=c,
+		                        $where=HTTP::IN_URL));
 	}