fix(game3): PC panel species scope fix and trainer-card var key fallback

Three follow-ups to the merge snapshot, kept as their own commit so the
review of the wave commit stays intact:

- The PC panel's left data panel broke in the merge: upstream inlines the
  egg-aware species read into frontPic while the M8 dedup had removed the
  duplicate local, so `sp` was referenced with no binding and the luacheck
  gate failed. One shared local sp = Pokemon.speciesOrEgg(hoveredMon) serves
  both the TV sprite and the stats card
  (pokefirered/src/pokemon_storage_system_data.c:1034, :1057,
  MON_DATA_SPECIES_OR_EGG).
- Trainer-card vars fall back to the stringified key: persist_sidecar and
  Flags.serialize write tostring(id) keys into session.vars, so a numeric miss
  used to read every var as 0.
- tests/game3_trainer_card_photo_tint_test.lua drives the whole Game Corner
  photo -> card tint chain (setvar -> UpdateTrainerCardPhotoIcons ->
  Flags.serialize/loadInto -> cardData) and pins c.monIconTint/c.monSpecies.

src/ui/game3/pc_chrome.lua

@@ -219,7 +219,12 @@ function PcChrome.drawLeftDataPanel(hoveredMon, hoverFrame)
 
   -- 1. Front Sprite in TV Screen (X: 10..73, Y: 19..80, W: 64, H: 61)
   -- pokefirered/src/pokemon_storage_system_data.c:1034, :1057 MON_DATA_SPECIES_OR_EGG
-  local sprite = Pokemon.frontPic(Pokemon.speciesOrEgg(hoveredMon))
+  -- Merge fix: upstream inlined the species read into frontPic (egg-aware) while
+  -- our M8 dedup removed block 2's duplicate local — one shared `sp` above
+  -- satisfies both sides (speciesOrEgg == speciesOf for every non-egg, and the
+  -- stats card never prints spName for an egg).
+  local sp = Pokemon.speciesOrEgg(hoveredMon)
+  local sprite = Pokemon.frontPic(sp)
   if sprite and sprite.image then
     love.graphics.setColor(1, 1, 1, 1)
     local sw, sh = sprite.image:getDimensions()

src/ui/game3/trainer_card.lua

@@ -342,7 +342,13 @@ local function get_var(session, varId)
     end
     if type(store.vars) == "table" then return tonumber(store.vars[varId]) or 0 end
   end
-  if session and type(session.vars) == "table" then return tonumber(session.vars[varId]) or 0 end
+  if session and type(session.vars) == "table" then
+    -- persist_sidecar/Flags.serialize write tostring(id) keys into session.vars;
+    -- a numeric miss must fall back to the string key or every var reads 0.
+    local v = session.vars[varId]
+    if v == nil then v = session.vars[tostring(varId)] end
+    return tonumber(v) or 0
+  end
   return 0
 end
 

tests/game3_trainer_card_photo_tint_test.lua

@@ -0,0 +1,148 @@
+-- End-to-end proof for the Game Corner photo -> trainer-card tint chain.
+-- Mirrors the real in-game wiring:
+--   setvar VAR_0x8004 (ctx.specialVars) -> special UpdateTrainerCardPhotoIcons (0x167)
+--   -> Flags.setVar into THE SAME store the card reads (Space.store in-game)
+--   -> Flags.serialize (game.save) -> Flags.loadInto (next boot)
+--   -> TrainerCard.cardData/gather -> c.monIconTint / c.monSpecies.
+-- Ground truth: saves/firered/slot1.lua (Sep 22 18:24) carries
+--   ["16450"]=2, ["16451"]=4, ["16452".."16456"]=0 with a 1-mon party (Charmander).
+
+package.path = "./?.lua;./?/init.lua;" .. package.path
+
+local Std = require("src.core.game3.scripting.stdscripts")
+local Natives = require("src.core.game3.scripting.natives")
+local Flags = require("src.core.game3.scripting.flags")
+local Schema = require("src.core.game3.save_schema_firered")
+local TrainerCard = require("src.ui.game3.trainer_card")
+
+local passed, failed = 0, 0
+local function check(cond, msg)
+  if cond then
+    passed = passed + 1
+    print("[ok] " .. msg)
+  else
+    failed = failed + 1
+    print("[FAIL] " .. msg)
+  end
+end
+
+local function checkEq(got, expected, msg)
+  if got == expected then
+    passed = passed + 1
+    print(string.format("[ok] %s (got %s)", msg, tostring(got)))
+  else
+    failed = failed + 1
+    print(string.format("[FAIL] %s: expected %s, got %s", msg, tostring(expected), tostring(got)))
+  end
+end
+
+local SPACE_KEY = "src.core.game3.scripting.space"
+local RT_KEY = "src.core.game3.runtime"
+
+local realLoadedSpace = package.loaded[SPACE_KEY]
+local realLoadedRt = package.loaded[RT_KEY]
+
+local function teardown()
+  package.loaded[SPACE_KEY] = realLoadedSpace
+  package.loaded[RT_KEY] = realLoadedRt
+end
+
+print("=== 1. Photo script path writes tint + species into THE store the card reads ===")
+local session, store, ctx
+do
+  session = Schema.newGame({ name = "RED" })
+  session.party = { { speciesId = 4, species = 4 } } -- user's save: one Charmander
+
+  store = Flags.newStore()
+  -- In-game both sides resolve Space from package.loaded; share one table so
+  -- scriptStore(ctx) (natives) and script_store() (trainer card) see ONE store.
+  package.loaded[SPACE_KEY] = { store = store, getStore = function() return store end }
+  package.loaded[RT_KEY] = { getSession = function() return session end }
+
+  ctx = {
+    flags = session.flags,
+    vars = session.vars,
+    specialVars = {},
+  }
+
+  -- Real setvar opcode path: Flags.setVar routes 0x80xx to ctx.specialVars.
+  Flags.setVar(store, ctx, 0x8004, 2) -- MON_ICON_TINT_PINK
+  local yielded = Natives.special(ctx, Std.SPECIAL.UpdateTrainerCardPhotoIcons)
+  check(yielded == false, "UpdateTrainerCardPhotoIcons completes without yielding")
+
+  checkEq(Flags.getVar(store, ctx, 0x4042), 2, "store 0x4042 tint idx is 2 (PINK)")
+  checkEq(Flags.getVar(store, ctx, 0x4043), 4, "store 0x4043 icon 1 is species 4")
+  for id = 0x4044, 0x4048 do
+    checkEq(Flags.getVar(store, ctx, id), 0, string.format("store 0x%04X empty slot", id))
+  end
+  checkEq(session.vars[0x4042], nil, "special vars do NOT leak into session.vars")
+
+  local c = TrainerCard.cardData(session)
+  checkEq(c.monIconTint, 2, "gather reads monIconTint=2 from the live store")
+  checkEq(c.monSpecies[1], 4, "gather reads monSpecies[1]=4 from the live store")
+end
+
+print("=== 2. Persist round trip: serialize (game.save) -> loadInto (next boot) ===")
+do
+  local snap = Flags.serialize(store)
+  checkEq(snap.vars["16450"], 2, "serialize writes string key [\"16450\"]=2 (save format)")
+  checkEq(snap.vars["16451"], 4, "serialize writes string key [\"16451\"]=4")
+
+  local bootStore = Flags.newStore()
+  Flags.loadInto(bootStore, snap)
+  checkEq(bootStore.vars[0x4042], 2, "loadInto restores numeric 0x4042=2")
+  checkEq(bootStore.vars[0x4043], 4, "loadInto restores numeric 0x4043=4")
+
+  package.loaded[SPACE_KEY] = { store = bootStore, getStore = function() return bootStore end }
+  local c = TrainerCard.cardData(session)
+  checkEq(c.monIconTint, 2, "card gather after reload reads monIconTint=2")
+  checkEq(c.monSpecies[1], 4, "card gather after reload reads monSpecies[1]=4")
+end
+
+print("=== 3. Store unavailable: session.vars fallback must read string keys ===")
+do
+  local snap = Flags.serialize(store)
+  session.vars = snap.vars -- save-format string keys, numeric miss
+  package.loaded[SPACE_KEY] = nil -- Space not resolvable -> script_store() nil
+
+  local c = TrainerCard.cardData(session)
+  checkEq(c.monIconTint, 2, "fallback reads [\"16450\"] -> monIconTint=2")
+  checkEq(c.monSpecies[1], 4, "fallback reads [\"16451\"] -> monSpecies[1]=4")
+end
+
+print("=== 4. Multi-mon party: all six species keys match snapshot order ===")
+do
+  local session4 = Schema.newGame({ name = "RED" })
+  session4.party = {
+    { speciesId = 1, species = 1 },
+    { speciesId = 4, species = 4 },
+    { speciesId = 7, species = 7 },
+    { speciesId = 25, species = 25 },
+    { speciesId = 133, species = 133 },
+    { speciesId = 152, species = 152 },
+  }
+  local store4 = Flags.newStore()
+  package.loaded[SPACE_KEY] = { store = store4, getStore = function() return store4 end }
+  package.loaded[RT_KEY] = { getSession = function() return session4 end }
+
+  local ctx4 = { flags = session4.flags, vars = session4.vars, specialVars = {} }
+  Flags.setVar(store4, ctx4, 0x8004, 2) -- MON_ICON_TINT_PINK
+  Natives.special(ctx4, Std.SPECIAL.UpdateTrainerCardPhotoIcons)
+
+  checkEq(Flags.getVar(store4, ctx4, 0x4042), 2, "multi-mon: store 0x4042 tint idx is 2")
+  local want = { 1, 4, 7, 25, 133, 152 }
+  for i = 1, 6 do
+    checkEq(Flags.getVar(store4, ctx4, 0x4042 + i), want[i],
+      string.format("multi-mon: store 0x%04X icon %d snapshot order", 0x4042 + i, i))
+  end
+  local c4 = TrainerCard.cardData(session4)
+  checkEq(c4.monIconTint, 2, "multi-mon: gather monIconTint=2")
+  for i = 1, 6 do
+    checkEq(c4.monSpecies[i], want[i], string.format("multi-mon: gather monSpecies[%d]", i))
+  end
+end
+
+teardown()
+
+print(string.format("Total: %d passed, %d failed", passed, failed))
+os.exit(failed == 0 and 0 or 1)