wip(0.S1, 0.S2): state records, mut and read-only state parameters, entry injection, module var refused; ludic migrate state

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/state/port_field.ludic

@@ -0,0 +1,12 @@
+# port_field.ludic — 0.S: a port member bound to a state's field, `money: Wallet.cash` - read
+# through the Wallet the runtime supplies, so a port needs no wrapper and no global.
+#
+# Running it prints:  40
+program PortField {
+  state Wallet { cash: int = 40 }
+  port Purse { money: fn() -> int }
+  bind Purse { money: Wallet.cash }
+  entry {
+    print(Purse.money())
+  }
+}