docs(code-runtime): fix remaining dunder/backend wording and document exports in README

- index.ts: RESERVED_ERROR_MEMBERS JSDoc now says `__x__` (non-empty
  middle), matching DUNDER_MEMBER and the derivative docs; and
  PORTABLE_RESERVED_WORDS is described as covering portable *target*
  languages (Python is a later-PR backend, not yet shipped).
- types.ts + type-equiv docs: CodeBindingNamespace.global points to
  RESERVED_BINDING_GLOBALS by name with an `e.g.` sample rather than
  enumerating the set (single home), no longer implying `__debug__` is a
  seeded slot.
- Agent Note: separate `__debug__` (CPython compile-time constant) from
  the seeded bootstrap globals.
- README (en/zh): document the four exported exclusion sets and the
  portable identifier/naming contract — no cross-package link needed.
- Regenerate cordis services catalog for the shifted source line.

docs/core-data-structures/code-runtime.md

@@ -99,9 +99,9 @@ interface CodeBindingNamespace {
    * words, so the same namespace list works against every backend regardless
    * of `language` — a JS-only spelling like `$tools` is rejected by design,
    * not just by the Python backend. Names that satisfy the identifier rule but
-   * name a backend-owned slot (`RESERVED_BINDING_GLOBALS`: `console`,
-   * `__dsh_main__`, `__builtins__`, `__name__`, `__debug__`) are also refused
-   * everywhere, since some backend seeds that slot in the program's namespace.
+   * name a backend-owned slot (`RESERVED_BINDING_GLOBALS`, e.g. `console`,
+   * `__dsh_main__`) are also refused everywhere; see its declaration for the
+   * exact set and why each entry is reserved.
    */
   global: string
   /** The callable members, keyed by the exact name the program calls. */