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/r989_trycallcollide_control/case.ww

@@ -0,0 +1,12 @@
+//ww:run-exit 42
+package beta;
+export type berr = !void;
+export fn op() (i32 | berr) = { return 5; };
+export fn user() (i32 | berr) = { let v: i32 = op()?; return v + 37; };
+package gamma;
+export type gerr1 = !void;
+export fn other() (i32 | gerr1) = { return 0; };
+package main;
+import beta;
+import gamma;
+fn main() int = { match (beta.user()) { case let n: i32 => return n: int; case berr => return 99; }; };