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/r695_match_bind_pair_letinit/case.ww

@@ -0,0 +1,15 @@
+//ww:run
+package main;
+type pair = struct { x: i64, y: i64, z: i64 };
+type tag = (pair | i32);
+fn main() i32 = {
+	let x: tag = (pair { x = 7i64, y = 11i64, z = 13i64 }: tag);
+	match (x) {
+	case let v: pair => {
+		let s: i64 = v.x + v.y + v.z;
+		if (s != 31i64) { return 1; };
+		return 0;
+	};
+	case let z: i32 => return 2;
+	};
+};