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/r71_match_spill_alias_error/case.ww

@@ -0,0 +1,16 @@
+//ww:run-exit 64
+package main;
+type oserror = !i64;
+fn kpath(p: str) (*u8 | oserror) = {
+	if (p.len >= 0) { return -36i64: oserror; };
+	let s: str = "A";
+	return s.ptr;
+};
+fn main() i32 = {
+	let q: str = "x";
+	match (kpath(q)) {
+	case let e: oserror => return ((e: i64): i32) + 100;
+	case let p: *u8 => return p[0]: i32;
+	};
+	return 0;
+};