test/wcc/data: grow the declarative compiler corpus to 1,224 fixtures

The r-prefixed waves absorb the runtime, reject, and byte-compare rows
of the migrated native carriers; each fixture is one directory with one
case.ww and a //ww:error, //ww:compile, //ww:run, or //ww:run-exit
directive covering both frontends.

test/wcc/data/r951_defdim_m4_end/case.ww

@@ -0,0 +1,10 @@
+//ww:run-exit 42
+package main;
+def M: i32 = 4;
+type t = struct { b: [M]u8, end: i32 };
+export fn main() i32 = {
+	let s: t;
+	s.b[3] = 9u8;
+	s.end = 42;
+	return s.end;
+};