kill: purge old-paradigm dist/platform binaries from tree

The generated C, amalgams, vendored runtime pins, and compiled binaries
from the Claude Code era are removed from the worktree. The El sources
survive; this tree is now source-only for the first-principles rebuild.

Per Principal direction 2026-08-19.

docs/v1/experiments/evidence/cycles/18-async-half-expressible/fixtures/probe.el

@@ -0,0 +1,12 @@
+extern fn el_await(h: Int) -> Int
+
+fn work(k: Int) -> Int {
+    return k * 2
+}
+
+fn main() {
+    let h: Int = work(21)
+    println("CALLER_CONTINUED")
+    let r: Int = el_await(h)
+    println("RESULT " + int_to_str(r))
+}