chore: stage diverged local work for merge

Includes Layer 1 S-expr dump, conformance tests, AST visitor,
seam audit fixes, and system specifications from local session.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/ocaml-core.yml

@@ -30,7 +30,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Setup OCaml
         uses: ocaml/setup-ocaml@v2
@@ -57,7 +57,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Setup OCaml
         uses: ocaml/setup-ocaml@v2