feat: generator interpreter for Python that waits for the player (Ren'Py)

Python containing renpy.input, narrator("..."), character calls, renpy.say,
renpy.pause, renpy.display_menu, renpy.with_statement or renpy.call_screen now
runs through loops, try, functions, methods and expressions.

Player
- python.ts: execG/evalG/callG run only the code that may wait (mayBlock);
  everything else stays on the synchronous fast path. A waiting call returns a
  BlockingCall; outside the generator interpreter it is an explicit error. The
  interpreter scope is set aside while the player decides
- engine: drives the generator and answers requests (dialogue, text input with
  length/allow/exclude, pause, choice menu, transition, call screen)
- renpy.show/hide/scene, transitions and transforms as Python values,
  Character(...) objects, Borders, set_tag_attributes

Converter
- blocking_names() lists game functions that may wait, transitively, and ships
  them as game.json "blocking"; character calls are allowed
- hide screen of an unknown screen is harmless; images defined by a parenthesised
  expression are supported

Hooked now passes the strict compatibility check (with Tomie and Twisted-Thoughts).
Tests: waiting.py fixture run through the generator interpreter; blocking-name analysis.

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

backend/app/converter/pipeline.py

@@ -19,6 +19,7 @@ from app.converter.compatibility import (
     CompatibilityError,
     Issue,
     audit_ir,
+    blocking_names,
     detect,
     require_supported_scripts,
 )
@@ -191,6 +192,7 @@ def convert_archive(archive: Path, filename: str, work: Path, progress: Progress
         "images": images,
         "transforms": data.transforms,
         "atl": data.atl,
+        "blocking": blocking_names(data),
         "screens": {name: data.screens[name] for name in sorted(_used_screens(data))},
         "styles": data.styles,
         "transitions": data.transitions,