ocaml: phase 4 open / include (+5 tests, 220 total)

Parser: open Path and include Path top-level decls; Path is Ctor (.Ctor)*.
Eval resolves via ocaml-resolve-module-path (same :con-as-module-lookup
escape hatch used by :field). open extends the env with the module's
bindings; include also merges into the surrounding module's exports
(when inside a struct...end).

Path resolver lets M.Sub.x work for nested modules. Phase 4 LOC ~165.

lib/ocaml/test.sh

@@ -555,6 +555,18 @@ cat > "$TMPFILE" << 'EPOCHS'
 (epoch 716)
 (eval "(ocaml-run-program \"module Pair = struct let make a b = (a, b) let swap p = match p with | (x, y) -> (y, x) end ;; Pair.swap (Pair.make 1 2)\")")
 
+;; ── open / include ─────────────────────────────────────────────
+(epoch 730)
+(eval "(ocaml-run-program \"module M = struct let x = 42 let f y = y + 1 end ;; open M ;; f x\")")
+(epoch 731)
+(eval "(ocaml-run-program \"module Math = struct let pi = 3 let sq x = x * x end ;; module Sphere = struct include Math let area r = 4 * pi * sq r end ;; Sphere.area 2\")")
+(epoch 732)
+(eval "(ocaml-run-program \"module M = struct let x = 1 end ;; module N = struct open M let y = x + 10 end ;; N.y\")")
+(epoch 733)
+(eval "(ocaml-run-program \"module Math = struct let pi = 3 let sq x = x * x end ;; module Sphere = struct include Math let area r = 4 * pi * sq r end ;; Sphere.pi\")")
+(epoch 734)
+(eval "(ocaml-run-program \"module M = struct let x = 1 let y = 2 end ;; module N = struct include M let z = x + y end ;; N.z\")")
+
 EPOCHS
 
 OUTPUT=$(timeout 60 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
@@ -883,6 +895,13 @@ check 714 "nested module Outer.Inner"    '99'
 check 715 "module rec fact 5"            '120'
 check 716 "module Pair.swap"             '("tuple" 2 1)'
 
+# ── open / include ──────────────────────────────────────────────
+check 730 "open M; f x"                  '43'
+check 731 "include Math; area"           '48'
+check 732 "module open inside"           '11'
+check 733 "Sphere.pi via include"        '3'
+check 734 "include M; N.z = x+y"         '3'
+
 TOTAL=$((PASS + FAIL))
 if [ $FAIL -eq 0 ]; then
   echo "ok $PASS/$TOTAL OCaml-on-SX tests passed"