feat: Ren'Py screens (screen/call screen/show screen) with actions and styles

Converter
- screens.py parses the screen language: containers (fixed, frame, vbox, hbox,
  grid, vpgrid, viewport, button, has), widgets (text, textbutton, imagebutton,
  add, bar ...), if/for/use/transclude, default, python, key, timer, on, inline ATL,
  conditional properties, and decompiled forms (unparenthesised operators,
  glued property values, comma separated actions)
- style statements, call/show/hide screen operators and Python-level
  renpy.show_screen are translated; only screens the game shows are audited,
  unused stock screens no longer block an import; undefined screens do
- ATL values may be computed at run time and transforms take parameters
  (at blink(0.2, 0.3)); blur property

Player
- screens.ts builds the DOM from the IR and rebuilds it on state changes;
  buttons with idle/hover/selected/insensitive states, tooltips, sounds, modal
  screens, timers and keys that survive re-rendering, saved with the save file
- Actions: Jump, Call, Return, SetVariable, Toggle*, SetScreenVariable, Show, Hide,
  ToggleScreen, Function, Play, Notify, If, Language, ShowMenu, OpenURL ...
- Crop/LiveCrop/Solid/Frame/Transform/DynamicDisplayable values, crop property,
  globals(), renpy.variant/change_language/seen_image, transition stubs

Tests: screen parser and runtime (linkedom DOM), screens fixture compiled from
tests/fixtures/screens.rpy. Docs: docs/SCREENS.md.

Twisted-Thoughts now passes the strict compatibility check.

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

frontend/tests/fixtures/screens.json

@@ -0,0 +1 @@
+{"screens":{"card":{"params":[{"n":"title","d":null,"kind":"p"}],"props":{},"defaults":[],"body":[{"w":"frame","args":[],"props":{},"body":[{"w":"vbox","args":[],"props":{},"body":[{"w":"text","args":[{"k":"name","id":"title"}],"props":{},"body":[]},{"c":"transclude"}]}]}]},"counter":{"params":[],"props":{},"defaults":[],"body":[{"w":"add","args":[{"k":"const","v":"#fff"}],"props":{"xysize":{"k":"tuple","v":[{"k":"const","v":10},{"k":"const","v":10}]}},"body":[]},{"w":"bar","args":[],"props":{"value":{"k":"call","f":{"k":"name","id":"VariableValue"},"a":[{"k":"const","v":"score"},{"k":"const","v":10}],"kw":{}},"xsize":{"k":"const","v":100},"vertical":{"k":"const","v":false}},"body":[]}]},"deck":{"params":[],"props":{},"defaults":[],"body":[{"c":"use","name":"card","args":[{"k":"const","v":"Deck"}],"kw":{},"body":[{"w":"text","args":[{"k":"bin","op":"+","l":{"k":"const","v":"child "},"r":{"k":"const","v":"one"}}],"props":{},"body":[]},{"w":"textbutton","args":[{"k":"const","v":"Pick"}],"props":{"action":{"k":"call","f":{"k":"name","id":"Return"},"a":[{"k":"const","v":1}],"kw":{}}},"body":[]}]},{"w":"add","args":[{"k":"const","v":"pic.png"}],"props":{"crop":{"k":"tuple","v":[{"k":"const","v":1},{"k":"const","v":2},{"k":"const","v":30},{"k":"const","v":40}]}},"body":[]},{"w":"add","args":[{"k":"const","v":"dot.png"}],"props":{"at":[{"props":{"alpha":0.0},"name":"blink","atl":"blink","args":[{"k":"const","v":0.02},{"k":"const","v":0.02}],"kw":{}}]},"body":[]},{"w":"add","args":[{"k":"const","v":"bg.png"}],"props":{"alpha":{"k":"const","v":0.0},"at":[{"props":{},"atl":{"steps":[{"op":"move","warp":"linear","t":0.1,"props":{"alpha":1.0}}],"repeat":null}}]},"body":[]},{"c":"on","event":"show","action":{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"shown"},{"k":"const","v":true}],"kw":{}}},{"c":"on","event":"hide","action":{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"hid"},{"k":"const","v":true}],"kw":{}}},{"w":"text","args":[{"k":"const","v":"x"}],"props":{"pos":{"k":"tuple","v":[{"k":"const","v":5},{"k":"const","v":6}]}},"body":[]},{"w":"vpgrid","args":[],"props":{"cols":{"k":"const","v":2}},"body":[{"w":"text","args":[{"k":"const","v":"a"}],"props":{},"body":[]},{"w":"text","args":[{"k":"const","v":"b"}],"props":{},"body":[]}]},{"w":"textbutton","args":[{"k":"const","v":"Language"}],"props":{"action":{"k":"list","v":[{"k":"call","f":{"k":"name","id":"Language"},"a":[{"k":"const","v":"ru"}],"kw":{}},{"k":"call","f":{"k":"name","id":"ToggleScreen"},"a":[{"k":"const","v":"counter"}],"kw":{}}]}},"body":[]},{"w":"add","args":[{"k":"call","f":{"k":"name","id":"Crop"},"a":[{"k":"tuple","v":[{"k":"const","v":0},{"k":"const","v":0},{"k":"const","v":8},{"k":"const","v":8}]},{"k":"const","v":"sprite.png"}],"kw":{}}],"props":{},"body":[]}]},"hud":{"params":[{"n":"day","d":{"k":"const","v":1},"kind":"p"}],"props":{"tag":{"k":"name","id":"hud"},"zorder":{"k":"const","v":5},"style_prefix":{"k":"const","v":"hud"}},"defaults":[["open",{"k":"const","v":false}]],"body":[{"w":"frame","args":[],"props":{"xalign":{"k":"const","v":0.0},"yalign":{"k":"const","v":0.0}},"body":[{"w":"vbox","args":[],"props":{"spacing":{"k":"const","v":6}},"body":[{"w":"text","args":[{"k":"const","v":"Day [day]"}],"props":{},"body":[]},{"c":"if","branches":[{"c":{"k":"cmp","l":{"k":"name","id":"money"},"ops":[">"],"r":[{"k":"const","v":10}]},"body":[{"w":"text","args":[{"k":"const","v":"Rich"}],"props":{},"body":[]}]},{"c":null,"body":[{"w":"text","args":[{"k":"const","v":"Poor"}],"props":{},"body":[]}]}]},{"c":"for","t":{"k":"name","id":"item"},"it":{"k":"name","id":"inventory"},"body":[{"w":"textbutton","args":[{"k":"name","id":"item"}],"props":{"action":{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"held"},{"k":"name","id":"item"}],"kw":{}}},"body":[]}]},{"w":"textbutton","args":[{"k":"const","v":"Menu"}],"props":{"action":{"k":"call","f":{"k":"name","id":"ToggleScreenVariable"},"a":[{"k":"const","v":"open"}],"kw":{}},"selected":{"k":"name","id":"open"}},"body":[]},{"c":"if","branches":[{"c":{"k":"name","id":"open"},"body":[{"w":"text","args":[{"k":"const","v":"open!"}],"props":{},"body":[]}]}]},{"w":"textbutton","args":[{"k":"const","v":"Go"}],"props":{"action":{"k":"list","v":[{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"went"},{"k":"const","v":true}],"kw":{}},{"k":"call","f":{"k":"name","id":"Jump"},"a":[{"k":"const","v":"elsewhere"}],"kw":{}}]}},"body":[]}]}]},{"c":"key","key":{"k":"const","v":"K_h"},"action":{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"hotkey"},{"k":"const","v":true}],"kw":{}}},{"c":"timer","delay":{"k":"const","v":0.02},"action":{"k":"call","f":{"k":"name","id":"SetVariable"},"a":[{"k":"const","v":"ticked"},{"k":"const","v":true}],"kw":{}},"repeat":null}]},"mood":{"params":[],"props":{},"defaults":[],"body":[{"w":"imagebutton","args":[],"props":{"action":{"k":"tuple","v":[{"k":"call","f":{"k":"name","id":Line truncated

frontend/tests/fixtures/screens.rpy

@@ -0,0 +1,94 @@
+# Source of screens.json. Regenerate from backend/ with:
+#   python -m tests.make_screens ../frontend/tests/fixtures/screens.rpy ../frontend/tests/fixtures/screens.json
+
+style hud_text:
+    size 30
+    color "#abc"
+
+style hud_button:
+    background "#123"
+    hover_background "#456"
+    padding (10, 4)
+
+transform fade_in:
+    alpha 0.0
+    linear 0.1 alpha 1.0
+
+screen hud(day=1):
+    tag hud
+    zorder 5
+    style_prefix "hud"
+    default open = False
+    frame:
+        xalign 0.0
+        yalign 0.0
+        vbox:
+            spacing 6
+            text "Day [day]"
+            if money > 10:
+                text "Rich"
+            else:
+                text "Poor"
+            for item in inventory:
+                textbutton item action SetVariable("held", item)
+            textbutton "Menu" action ToggleScreenVariable("open") selected open
+            if open:
+                text "open!"
+            textbutton "Go" action [SetVariable("went", True), Jump("elsewhere")]
+    key "K_h" action SetVariable("hotkey", True)
+    timer 0.02 action SetVariable("ticked", True)
+
+screen shop(item="none"):
+    modal True
+    imagebutton auto "buy_%s.png" action Return(item) at fade_in
+    textbutton "Cancel" action Return(None) sensitive can_cancel
+
+screen counter():
+    add "#fff" xysize (10, 10)
+    bar value VariableValue("score", 10) xsize 100
+
+transform blink(delay, cycle=1.0):
+    alpha 0.0
+    pause delay
+    linear cycle alpha 1.0
+
+screen card(title):
+    frame:
+        has vbox
+        text title
+        transclude
+
+screen deck():
+    use card("Deck"):
+        text "child " + "one"
+        textbutton "Pick" action Return(1)
+    add "pic.png" crop(1, 2, 30, 40)
+    add "dot.png" at blink(0.02, 0.02)
+    add "bg.png":
+        alpha 0.0
+        linear 0.1 alpha 1.0
+    on "show" action SetVariable("shown", True)
+    on "hide" action SetVariable("hid", True)
+    text "x" pos(5, 6)
+    vpgrid:
+        cols 2
+        text "a"
+        text "b"
+    textbutton "Language" action [Language("ru"), ToggleScreen("counter")]
+    add Crop((0, 0, 8, 8), "sprite.png")
+
+screen mood():
+    imagebutton:
+        if money > 10:
+            idle "rich.png"
+        else:
+            idle "poor.png"
+        action SetVariable("mood_clicked", 1), SetVariable("mood_done", True)
+
+label start:
+    show screen mood
+    show screen deck
+    show screen hud(2)
+    call screen shop("sword")
+    show screen counter
+    return