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/r978_u32_mod_high_bit_set/case.ww

@@ -0,0 +1,8 @@
+//ww:run-exit 42
+package main;
+fn main() i32 = {
+	let a: u32 = 0x80000001u32;
+	let b: u32 = 2u32;
+	if (a % b == 1u32) { return 42; };
+	return 0;
+};