wip(0.S3): ui blocks, scene on enter/exit, hooks, machines over a state's field, namespace and engine-system injection; a reference out of a read-only state or a module let is read-only; deps counts writes into another module's state; the rejected examples hold states

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

selfhost/frontend/ast.ludic

@@ -92,6 +92,7 @@ property Node {
   pos:  int = -1              # 0.S: byte offset of its first token in its file (-1: generated)
   pos2: int = -1              # 0.S: a second place a rewrite needs (a declaration's end, a '(')
   mg:   int = -1              # 0.S2: its index in the migration's tables (migrate.ludic)
+  vw:   int = -1              # 0.S: the view a function was generated for or written in
 }
 
 # every node remembers where it was parsed (file + the line of the token the
@@ -104,6 +105,7 @@ function node(kind: int) -> Node {
   if g_parsing and pi < len(toks) {
     n.line = toks[pi].line
     n.pos = toks[pi].pos
+    if g_gen_nodes { n.pos = -1 }            # made by the compiler, not read from a file
   }
   return n
 }