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/19-a-convention-is-not-a-gate/fixtures/p8_intermediate.patch

@@ -0,0 +1,18 @@
+diff --git a/lang/runtime/el_runtime.c b/lang/runtime/el_runtime.c
+index 73c04e09..f2fbcb6a 100644
+--- a/lang/runtime/el_runtime.c
++++ b/lang/runtime/el_runtime.c
+@@ -18306,12 +18306,7 @@ static int el_bin_lookup(const void* p, size_t* out_len) {
+ static size_t el_input_len(const char* s) {
+     size_t n;
+     if (el_bin_lookup(s, &n)) return n;
+-    /* The FALLBACK is the hazard, not the tagged lookup. A NULL check does not
+-     * establish that a slot is a pointer: el_val_t carries integers too, so
+-     * strlen() on `sha256_hex(50000)` walks address 50000. Guarding the tagged
+-     * path alone left this untouched and the SIGSEGV unchanged -- measured. */
+-    if (!looks_like_heap_obj((el_val_t)(uintptr_t)s)) return 0;
+-    return strlen(s);
++    return s ? strlen(s) : 0;
+ }
+ 
+ /* ─── SHA-256 (Brad Conte / public domain) ──────────────────────────────── */

docs/v1/experiments/evidence/cycles/19-a-convention-is-not-a-gate/fixtures/p8_reconstruct_intermediate.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python3
+# p8_patch.py — construct the P8 INTERMEDIATE state described in cycle 19.
+#
+# Cycle 19's P8 says: routing el_bin_lookup through the gate did NOT fix the
+# SIGSEGV, because the FALLBACK (el_input_len's `s ? strlen(s) : 0`) was the
+# hazard. That intermediate state was never committed, so no historical
+# artifact exists for it. This constructs it TODAY, from 9a6c161, by reverting
+# ONLY the el_input_len hunk back to its cb7289f form and leaving the new
+# el_bin_lookup gate in place. It is labelled a re-derivation, not a recovery.
+p = "/tmp/rerun-v1b-19-p8/lang/runtime/el_runtime.c"
+s = open(p).read()
+new = """static size_t el_input_len(const char* s) {
+    size_t n;
+    if (el_bin_lookup(s, &n)) return n;
+    /* The FALLBACK is the hazard, not the tagged lookup. A NULL check does not
+     * establish that a slot is a pointer: el_val_t carries integers too, so
+     * strlen() on `sha256_hex(50000)` walks address 50000. Guarding the tagged
+     * path alone left this untouched and the SIGSEGV unchanged -- measured. */
+    if (!looks_like_heap_obj((el_val_t)(uintptr_t)s)) return 0;
+    return strlen(s);
+}"""
+old = """static size_t el_input_len(const char* s) {
+    size_t n;
+    if (el_bin_lookup(s, &n)) return n;
+    return s ? strlen(s) : 0;
+}"""
+assert s.count(new) == 1, "expected exactly one el_input_len, found %d" % s.count(new)
+open(p, "w").write(s.replace(new, old))
+print("P8 intermediate constructed: el_bin_lookup KEEPS the new gate,")
+print("el_input_len reverted to the cb7289f fallback `s ? strlen(s) : 0`")

docs/v1/experiments/evidence/cycles/19-a-convention-is-not-a-gate/fixtures/sha256_hex_int.el

@@ -0,0 +1,3 @@
+fn main() {
+    println(sha256_hex(50000))
+}

docs/v1/experiments/evidence/cycles/19-a-convention-is-not-a-gate/fixtures/sha256_hex_legit.el

@@ -0,0 +1,3 @@
+fn main() {
+    println(sha256_hex("abc"))
+}