test: migrate Fam13 misc checker/coercion value tests to @test (#5-C6)

Final fold-2 chunk. The 12 Fam13 single-file value drivers move from
test/wcc/*_run.c into in-language @test row-tables under test/lang/:

- value rows -> test/lang/*_test.ww (12 files)
- reject rows -> runww //ww:error carriers (13, dual-stage non-vacuous)
- nullable abort rows -> runww //ww:run-exit 1 carriers (3)
- 953_globalslice_arg -> _runonly (cs!=ww checker divergence, #28)
- 788 value_not_type_neg + 953_arrlit_slice reject_assign kept as slim
  rc-only .c pins (divergent-diag dual-reject, mutation-gated); 788 #29

Coverage parity verified row-by-row vs each retired driver; advisor-
ratified carve taxonomy; two-round reviewed. Floor ratchet follows.

test/wcc/data/a2s_mismatch_callarg/case.ww

@@ -0,0 +1,9 @@
+//ww:error "not assignable"
+// #258 carrier: element-type mismatch at a call-arg borrow; both stages refuse.
+// From test/wcc/953_arraytoslice_run.c mismatch_callarg.
+package main;
+fn f(s: []u8) i32 = { return 0; };
+export fn main() i32 = {
+	let a: [4]i32 = [1, 2, 3, 4];
+	return f(a);
+};

test/wcc/data/a2s_mismatch_let/case.ww

@@ -0,0 +1,9 @@
+//ww:error "not assignable"
+// #258 carrier: an element-type mismatch ([4]i32 -> []u8) is NOT a borrow;
+// both stages must refuse it. From test/wcc/953_arraytoslice_run.c mismatch_let.
+package main;
+export fn main() i32 = {
+	let a: [4]i32 = [1, 2, 3, 4];
+	let s: []u8 = a;
+	return 0;
+};

test/wcc/data/arrlit_slice_reject_call/case.ww

@@ -0,0 +1,9 @@
+//ww:error "not assignable"
+// #31/#33 carrier: an array-lit slice borrow in CALL-ARG position must REJECT
+// (supported only at a `let` init). From test/wcc/953_arrlit_slice_run.c
+// reject_call.
+package main;
+fn sum(s: []i32) i32 = { return s[0]; };
+export fn main() i32 = {
+	return sum([1, 2, 3]);
+};

test/wcc/data/arrlit_slice_reject_oob/case.ww

@@ -0,0 +1,8 @@
+//ww:error "array element out of range"
+// #25 carrier: an out-of-range element in a slice array-lit init must REJECT on
+// both stages. From test/wcc/953_arrlit_slice_run.c reject_oob.
+package main;
+export fn main() i32 = {
+	let q: []u8 = [256, 1];
+	return q[0]: i32;
+};

test/wcc/data/arrlit_slice_reject_ret/case.ww

@@ -0,0 +1,8 @@
+//ww:error "not assignable"
+// #31/#33 carrier: an array-lit slice borrow in RETURN position must REJECT.
+// From test/wcc/953_arrlit_slice_run.c reject_ret.
+package main;
+fn mk() []i32 = { return [1, 2, 3]; };
+export fn main() i32 = {
+	return mk()[0];
+};

test/wcc/data/arrnarrow_def_over/case.ww

@@ -0,0 +1,6 @@
+//ww:error "array element out of range"
+// #251 carrier: out-of-range element at a def (was a ww over-accept). From
+// test/wcc/951_arrlit_elem_narrow_run.c def_over.
+package main;
+def D: [2]u8 = [300, 1];
+export fn main() i32 = { return D[0]: i32; };

test/wcc/data/arrnarrow_def_str/case.ww

@@ -0,0 +1,6 @@
+//ww:error "not assignable"
+// #251 carrier: str element at a def (was a ww over-accept). From
+// test/wcc/951_arrlit_elem_narrow_run.c def_str.
+package main;
+def D: [2]u8 = ["x", "y"];
+export fn main() i32 = { return 0; };

test/wcc/data/arrnarrow_let_over/case.ww

@@ -0,0 +1,5 @@
+//ww:error "array element out of range"
+// #251 carrier: out-of-range int array-lit element at a local let must REJECT
+// on both stages. Migrated from test/wcc/951_arrlit_elem_narrow_run.c let_over.
+package main;
+export fn main() i32 = { let a: [2]u8 = [300, 1]; return a[0]: i32; };

test/wcc/data/arrnarrow_let_str/case.ww

@@ -0,0 +1,5 @@
+//ww:error "not assignable"
+// #251 carrier: str array-lit element to a [N]u8 let must REJECT (non-foldable
+// element-type mismatch). From test/wcc/951_arrlit_elem_narrow_run.c let_str.
+package main;
+export fn main() i32 = { let a: [2]u8 = ["x", "y"]; return a[0]: i32; };

test/wcc/data/arrnarrow_struct_over/case.ww

@@ -0,0 +1,7 @@
+//ww:error "array element out of range"
+// #251 carrier: out-of-range element at a struct-field init (was a ww
+// over-accept). From test/wcc/951_arrlit_elem_narrow_run.c struct_over.
+package main;
+type enc = struct { m: [2]u8 };
+let E: enc = enc { m = [300, 1] };
+export fn main() i32 = { return E.m[0]: i32; };

test/wcc/data/arrnarrow_struct_str/case.ww

@@ -0,0 +1,7 @@
+//ww:error "not assignable"
+// #251 carrier: str element at a struct-field init (was a ww over-accept).
+// From test/wcc/951_arrlit_elem_narrow_run.c struct_str.
+package main;
+type enc = struct { m: [2]u8 };
+let E: enc = enc { m = ["x", "y"] };
+export fn main() i32 = { return E.m[0]: i32; };

test/wcc/data/forrange_arr_field_base/case.ww

@@ -0,0 +1,12 @@
+//ww:error "for-range over a non-ident array base unwired (#70)"
+// #70 carrier: for-range over a non-ident ARRAY base (struct field) stays
+// LOUD on both stages until a consumer wires it. Migrated from
+// test/wcc/937_forrange_fieldbase_run.c reject_arr_field row.
+package main;
+type holder = struct { arr: [3]i64, n: i64 };
+export fn main() i32 = {
+	let h: holder = holder { arr = [1, 2, 3], n = 0 };
+	let s: i64 = 0;
+	for (let v .. h.arr) { s += v; };
+	return (s: i32);
+};

test/wcc/data/forrange_deref_base/case.ww

@@ -0,0 +1,13 @@
+//ww:error "for-range over a deref base unwired (#11)"
+// #70 carrier: for-range over a *p deref base stays LOUD on both stages
+// (the #11 deref-spine family — cgexpr does not deliver the slice header).
+// Migrated from test/wcc/937_forrange_fieldbase_run.c reject_deref row.
+package main;
+export fn main() i32 = {
+	let xs: []i64;
+	append(xs, 1);
+	let q: *[]i64 = &xs;
+	let s: i64 = 0;
+	for (let v .. *q) { s += v; };
+	return (s: i32);
+};

test/wcc/data/nullable_asrt_void_fail/case.ww

@@ -0,0 +1,14 @@
+//ww:run-exit 1
+// #17 (F4) carrier: `e as T` on a null (*int|void) operand must ABORT (exit 1),
+// not silently pass. Hare guarantees a failed type-assert calls rt::abort (drew)
+// — not a row in @test (an abort kills `ww test`). The clean twin asrt_ptr_ok in
+// test/lang/nullable_assert_test.ww carries the abort-arm byte-id (ken: ww emits
+// the check-and-abort arm INLINE, so a wwstage regression diverges that twin);
+// the non-redundant dimension here is the RUNTIME abort. Underlying fix was
+// wwstage cgen (cgtypeassert nullable arm). From 949_nullable_assert_run.c.
+package main;
+export fn main() i32 = {
+	let p: (*int|void) = void;
+	let q = p as *int;
+	return 50;
+};

test/wcc/data/nullable_asrt_void_target_fail/case.ww

@@ -0,0 +1,12 @@
+//ww:run-exit 1
+// #17 (F4) carrier: a valid ptr `as void` must ABORT (exit 1) — the void
+// polarity of the type-assert. Clean twin asrt_void_target_ok carries the
+// abort-arm byte-id; this pins the runtime abort fires. From
+// 949_nullable_assert_run.c (drew: rt::abort is a real Hare guarantee).
+package main;
+export fn main() i32 = {
+	let x: int = 5;
+	let p: (*int|void) = &x;
+	let z = p as void;
+	return 7;
+};

test/wcc/data/nullable_tryunw_null/case.ww

@@ -0,0 +1,12 @@
+//ww:run-exit 1
+// #15 (F4) carrier: `p!` on a null (*int|void) must ABORT (exit 1), not treat
+// null as success and deref (SEGV pre-fix). Clean twin tryunw_valid in
+// test/lang/nullable_try_test.ww carries the abort-arm byte-id; this pins the
+// runtime abort. Underlying fix was wwstage cgen (cgtryunw nullable arm). From
+// 949_nullable_try_run.c.
+package main;
+fn h(p: (*int|void)) int = { let q = p!; return *q; };
+export fn main() i32 = {
+	let r = h(void);
+	return 50;
+};