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/r776_borrowedread_view_eof/case.ww

@@ -0,0 +1,22 @@
+//ww:run-exit 47
+// Migrated from 776_memio_vstream_run row borrowedread_view_eof.
+package main;
+import memio;
+import io;
+import os;
+export fn main() i32 = {
+    let seed: [4]u8;
+    seed[0] = 1u8; seed[1] = 2u8; seed[2] = 3u8; seed[3] = 4u8;
+    let st: memio.stream = memio.dynamicfrom(seed[0:4]);
+    let br = memio.borrowedread(&st, 3);
+    match (br) {
+    case let b: []u8 => { if (b.len != 3 || b[0] != 1u8 || b[2] != 3u8) { return 91; }; };
+    case io.eof => { return 92; };
+    };
+    let br2 = memio.borrowedread(&st, 2);
+    match (br2) {
+    case let b: []u8 => { return 93; };
+    case io.eof => { return 47; };
+    };
+    return 99;
+};