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_loopcap_at_16/case.ww

@@ -0,0 +1,13 @@
+//ww:run
+// Exactly LOOP_MAX nested loops remain accepted.
+package main;
+export fn main() i32 = {
+	let n: i32 = 0;
+	for (n < 1) { for (n < 1) { for (n < 1) { for (n < 1) {
+	for (n < 1) { for (n < 1) { for (n < 1) { for (n < 1) {
+	for (n < 1) { for (n < 1) { for (n < 1) { for (n < 1) {
+	for (n < 1) { for (n < 1) { for (n < 1) { for (n < 1) {
+		n = 1;
+	}; }; }; }; }; }; }; }; }; }; }; }; }; }; }; };
+	return 0;
+};