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_wide4_letinit/case.ww

@@ -0,0 +1,16 @@
+//ww:run
+package main;
+type wide = struct { a: i64, b: i64, c: i64, d: i64 };
+type tag = (wide | i32);
+fn main() i32 = {
+	let x: tag = (wide { a = 1i64, b = 2i64, c = 4i64,
+		d = 24i64 }: tag);
+	match (x) {
+	case let v: wide => {
+		let s: i64 = v.a + v.b + v.c + v.d;
+		if (s != 31i64) { return 1; };
+		return 0;
+	};
+	case let z: i32 => return 2;
+	};
+};