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/r809idx_tuple_elem/case.ww

@@ -0,0 +1,3 @@
+//ww:run-exit 34
+package main;
+export fn main() i32 = { let a: [2](u64, u64); a[1] = (3u64, 4u64); let t: (u64, u64) = a[1]; return (t.0 * 10u64 + t.1): i32; };