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/r670_f64_9args/case.ww

@@ -0,0 +1,4 @@
+//ww:run-exit 42
+package main;
+fn s9f(a: f64, b: f64, c: f64, d: f64, e: f64, f: f64, g: f64, h: f64, i: f64) f64 = { return a + b + c + d + e + f + g + h + i; };
+fn main() i32 = { let r: f64 = s9f(1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0); if ((r: i64) == 45i64) { return 42; }; return 0; };