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/r989_libprecond_u64n_valid/case.ww

@@ -0,0 +1,9 @@
+//ww:run
+package main;
+import math.random;
+export fn main() int = {
+	let g: random.random = random.init(1u64);
+	let x: u64 = random.u64n(&g, 10u64);
+	if (x >= 10u64) { return 1; };
+	return 0;
+};