lib/strconv: stoi/stou/stoz machine-word int parse (strconv-int fold-1 C2)

Add the int/uint/size entry points (ref/hare/strconv/stoi.ha:53,
stou.ha:107,113). Hare clamps to types::INT_MIN/MAX, UINT_MAX, SIZE_MAX
via stoiminmax/stoumax; ww's int/uint/size are 8B machine words
(INT/UINT/SIZE limits == I64/U64 per lib/types/types.ww:30-37), so the
clamp is a no-op — the full i64/u64 range parses with no spurious
overflow. Documented at-site (the bound consts are package-private, so
inlining them would just re-encode I64/U64_MAX).

Tests: extend inttest.ww with test_stoi_stou_stoz — value path, sign,
overflow pass-through, and the no-clamp fidelity (I64_MAX/U64_MAX parse
without overflow) plus hex/bin bases through the shared parseint core.

combined.ww regen: w6c + wwdump main.combined.ww.

selfhost/cmd/w6c/main.combined.ww

@@ -6234,6 +6234,23 @@ export fn stoi8(s: str, b: base) (i8 | invalid | overflow) = {
 	return 0: invalid;
 };
 
+// stoi — parse signed base-b number into an int. Mirrors Hare's
+// strconv::stoi (ref/hare/strconv/stoi.ha:53), which clamps to
+// types::INT_MIN/INT_MAX via stoiminmax. ww's int is a machine word
+// (8B → i64-width, so INT_MIN/INT_MAX == I64_MIN/I64_MAX per
+// lib/types/types.ww:30-31), so stoi64's result always fits and the
+// clamp is a no-op — omitted, not inlined (the bound consts are
+// package-private; see the inline note at mulshift32 in ftos.ww).
+export fn stoi(s: str, b: base) (int | invalid | overflow) = {
+	let r = stoi64(s, b);
+	match (r) {
+	case let v: i64      => return v: int;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
 export fn stou32(s: str, b: base) (u32 | invalid | overflow) = {
 	let r = stou64(s, b);
 	match (r) {
@@ -6273,6 +6290,34 @@ export fn stou8(s: str, b: base) (u8 | invalid | overflow) = {
 	return 0: invalid;
 };
 
+// stou — parse unsigned base-b number into a uint. Mirrors Hare's
+// strconv::stou (ref/hare/strconv/stou.ha:107), which clamps to
+// types::UINT_MAX via stoumax. ww's uint is a machine word (8B →
+// u64-width, so UINT_MAX == U64_MAX per lib/types/types.ww:33), so
+// stou64's result always fits and the clamp is a no-op.
+export fn stou(s: str, b: base) (uint | invalid | overflow) = {
+	let r = stou64(s, b);
+	match (r) {
+	case let v: u64      => return v: uint;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
+// stoz — parse unsigned base-b number into a size. Mirrors Hare's
+// strconv::stoz (ref/hare/strconv/stou.ha:113). ww's size is u64-width
+// (SIZE_MAX == U64_MAX per lib/types/types.ww:37), so the clamp is a no-op.
+export fn stoz(s: str, b: base) (size | invalid | overflow) = {
+	let r = stou64(s, b);
+	match (r) {
+	case let v: u64      => return v: size;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
 // f64tos — graduated to the Ryū shortest-round-trippable implementation
 // in ftos.ww (strconv #106 fold-5). The old lossy fixed-point version
 // (6 fractional digits, "huge" fallback ≥9e18, no NaN/Inf) was deleted

selfhost/cmd/wwdump/main.combined.ww

@@ -6234,6 +6234,23 @@ export fn stoi8(s: str, b: base) (i8 | invalid | overflow) = {
 	return 0: invalid;
 };
 
+// stoi — parse signed base-b number into an int. Mirrors Hare's
+// strconv::stoi (ref/hare/strconv/stoi.ha:53), which clamps to
+// types::INT_MIN/INT_MAX via stoiminmax. ww's int is a machine word
+// (8B → i64-width, so INT_MIN/INT_MAX == I64_MIN/I64_MAX per
+// lib/types/types.ww:30-31), so stoi64's result always fits and the
+// clamp is a no-op — omitted, not inlined (the bound consts are
+// package-private; see the inline note at mulshift32 in ftos.ww).
+export fn stoi(s: str, b: base) (int | invalid | overflow) = {
+	let r = stoi64(s, b);
+	match (r) {
+	case let v: i64      => return v: int;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
 export fn stou32(s: str, b: base) (u32 | invalid | overflow) = {
 	let r = stou64(s, b);
 	match (r) {
@@ -6273,6 +6290,34 @@ export fn stou8(s: str, b: base) (u8 | invalid | overflow) = {
 	return 0: invalid;
 };
 
+// stou — parse unsigned base-b number into a uint. Mirrors Hare's
+// strconv::stou (ref/hare/strconv/stou.ha:107), which clamps to
+// types::UINT_MAX via stoumax. ww's uint is a machine word (8B →
+// u64-width, so UINT_MAX == U64_MAX per lib/types/types.ww:33), so
+// stou64's result always fits and the clamp is a no-op.
+export fn stou(s: str, b: base) (uint | invalid | overflow) = {
+	let r = stou64(s, b);
+	match (r) {
+	case let v: u64      => return v: uint;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
+// stoz — parse unsigned base-b number into a size. Mirrors Hare's
+// strconv::stoz (ref/hare/strconv/stou.ha:113). ww's size is u64-width
+// (SIZE_MAX == U64_MAX per lib/types/types.ww:37), so the clamp is a no-op.
+export fn stoz(s: str, b: base) (size | invalid | overflow) = {
+	let r = stou64(s, b);
+	match (r) {
+	case let v: u64      => return v: size;
+	case let e: invalid  => return e;
+	case let e: overflow => return e;
+	};
+	return 0: invalid;
+};
+
 // f64tos — graduated to the Ryū shortest-round-trippable implementation
 // in ftos.ww (strconv #106 fold-5). The old lossy fixed-point version
 // (6 fractional digits, "huge" fallback ≥9e18, no NaN/Inf) was deleted