ww: import toolchain — C bootstrap + ww-side self-host (phases 0-10)

C bootstrap (phases 0-9):
  cmd/wwc, cmd/6c, cmd/6a, cmd/6l, cmd/ww, rt, lib/*.

ww-side self-host (phase 10):
  selfhost/cmd/wwc — ww-cgen frontend; bootstrap fixed point.
  selfhost/cmd/6a  — assembler; byte-identical to C 6a (test 991).
  selfhost/cmd/6l  — linker w/ archive (.a) support; byte-identical
                     to C 6l (test 992).
  selfhost/cmd/ww  — driver (build/run/version); byte-identical to
                     C ww (test 993).

make test: 15/15. make bootstrap: ww2.s == ww3.s, ww2.o == ww3.o,
ww2 == ww3 byte-identical, with the full ww-tooled chain.

lib/sort/sort.ww

@@ -0,0 +1,27 @@
+// sort — sorting helpers. The data is reached through a vtable so the
+// algorithm stays generic without language-level generics.
+
+type slice = struct {
+	ctx:  *void,
+	len:  i32,
+	less: fn(s: *slice, i: i32, j: i32) bool,
+	swap: fn(s: *slice, i: i32, j: i32) void,
+};
+
+// Insertion sort, fine for small inputs and stable. We'll grow into
+// quicksort later when we have heavier tests.
+export fn sort(s: *slice) void = {
+	let i: i32 = 1;
+	for (i < s.len) {
+		let j: i32 = i;
+		for (j > 0) {
+			if (s.less(s, j, j - 1)) {
+				s.swap(s, j, j - 1);
+				j -= 1;
+			} else {
+				j = 0;
+			};
+		};
+		i += 1;
+	};
+};