fix(challenge,scene): challenge id auto-detect, real ScRsp ids, teleport ownership

Round-2 fixes from the 01:44-01:53 client session:

- StartChallenge (MoC/PF/AS normal start) decoded challenge_id=0 -> client
  retried and aborted. detectChallengeID scans top-level varints for the
  first plausible id (challenge_data + known mode ranges) when the strict
  tag-14 decode misses; payload hexdump logged when still 0
- StartChallengeScRsp now carries stage_info (tag 13) with boss node buff
  echo, per the 4.6.51 proto
- GetSwitchHandData replies 8108 (the real ScRsp) - 8104 is
  SwitchHandStartCsReq, we were sending a request id back at the client
- GetSceneMapInfo: strict proto parse failed on some payloads (layout
  drift) which stalled the map UI ('no pillars / navigation loading') -
  now a raw handler with a lenient wire walk fallback + hexdump logging
- teleport destination ('AA teleport landed in AP'): teleport ids repeat
  on every floor and teleports.json was scanned globally in random map
  order. Map clicks now resolve floor-first via scene_identifier, and the
  global id scan never touches teleports.json
- tierce: arena 3014101 -> 3000101 fallback (client has no MapEntrance
  3014101), same as StartChallenge

internal/gameserver/handlers_challenge_flow.go

@@ -567,10 +567,64 @@ func dedupeTruncate4(in []uint32) []uint32 {
 	return out
 }
 
+// looksLikeChallengeID: known challenge-id ranges across endgame modes.
+func looksLikeChallengeID(v uint64) bool {
+	switch {
+	case v >= 101 && v <= 119, v == 900,
+		v >= 1001 && v <= 1035,
+		v >= 2001 && v <= 2025,
+		v >= 3001 && v <= 3020,
+		v >= 5000 && v <= 5700,   // MoC floors incl. 4.6 phases
+		v >= 20000 && v <= 20300, // Pure Fiction
+		v >= 30000 && v <= 30300: // Apocalyptic Shadow
+		return true
+	}
+	cd := getChallengeData()
+	_, okC := cd.Challenges[uint32(v)]
+	_, okT := cd.Tierce[uint32(v)]
+	return okC || okT
+}
+
+// detectChallengeID: when the strict decoder misses the challenge id (field
+// layout drift between client builds), scan top-level varint fields for the
+// first value that looks like a challenge id.
+func detectChallengeID(payload []byte) (uint32, int) {
+	buf := payload
+	for len(buf) > 0 {
+		tag, n := readUvarint(buf)
+		if n == 0 {
+			break
+		}
+		buf = buf[n:]
+		wireType := uint32(tag & 0x7)
+		if wireType == 0 {
+			v, n2 := readUvarint(buf)
+			if n2 == 0 {
+				break
+			}
+			buf = buf[n2:]
+			if looksLikeChallengeID(v) {
+				return uint32(v), int(tag >> 3)
+			}
+		} else {
+			skipWireField(wireType, &buf)
+		}
+	}
+	return 0, 0
+}
+
 // handleStartChallenge ports handle_start_challenge: respond cmd 1787 with
-// retcode(3) + cur_challenge(5) + lineup_list(6) + scene(10).
+// retcode(3) + cur_challenge(5) + lineup_list(6) + scene(10) + stage_info(13).
 func handleStartChallenge(s *Session, payload []byte) error {
 	req := decodeStartChallengeReq(payload)
+	if req.challengeID == 0 {
+		if id, field := detectChallengeID(payload); id != 0 {
+			Log("handle_start_challenge: strict decode missed, detected challenge_id=" + itoa(int(id)) + " at field " + itoa(field))
+			req.challengeID = id
+		} else {
+			PacketLog("[CHALLENGE] challenge_id=0 payload=" + hexDump(payload, 128))
+		}
+	}
 	Log("handle_start_challenge: challenge_id=" + itoa(int(req.challengeID)))
 
 	chosenAvatars := req.firstAvatars
@@ -592,12 +646,13 @@ func handleStartChallenge(s *Session, payload []byte) error {
 		}
 	}
 
-	// fallback to the standard arena when the mapped one is missing from res
-	if res, err := common.GameRes(); err == nil {
-		if !mapHasEntry(res, entrance) {
-			Log("[CHALLENGE] Arena entrance missing in res.json, fallback to 3000101")
-			entrance = 3000101
-		}
+	// the 4.6.51 client has no MapEntrance 3014101 (Rust lesson: Lua
+	// GotoMapParam nil -> stuck loading) even though res.json has it
+	if entrance == 3014101 {
+		entrance = 3000101
+	} else if res, err := common.GameRes(); err == nil && !mapHasEntry(res, entrance) {
+		Log("[CHALLENGE] Arena entrance missing in res.json, fallback to 3000101")
+		entrance = 3000101
 	}
 
 	Log("[CHALLENGE] Start: challenge_id=" + itoa(int(req.challengeID)) + " (mapped " + itoa(int(baseID)) + ")")
@@ -640,6 +695,20 @@ func handleStartChallenge(s *Session, payload []byte) error {
 		return err
 	}
 
+	// 4.6.51: StartChallengeScRsp.stage_info (tag 13) - boss node info echoes
+	// the selected buff so the client can set up the challenge UI
+	stageInfo := &goproto.ChallengeStageInfo{}
+	if req.buffID != 0 {
+		stageInfo.BossInfo = &goproto.ChallengeBossInfo{
+			FirstNode:  &goproto.ChallengeBossSingleNodeInfo{BuffId: req.buffID},
+			SecondNode: &goproto.ChallengeBossSingleNodeInfo{BuffId: req.buffID},
+		}
+	}
+	stageBuf, err := proto.Marshal(stageInfo)
+	if err != nil {
+		return err
+	}
+
 	var body []byte
 	body = append(body, 0x18, 0x00) // tag 3: retcode = 0
 	body = append(body, 0x2A)       // tag 5: cur_challenge
@@ -651,6 +720,9 @@ func handleStartChallenge(s *Session, payload []byte) error {
 	body = append(body, 0x52) // tag 10: scene
 	body = appendUvarint(body, uint64(len(sceneBuf)))
 	body = append(body, sceneBuf...)
+	body = append(body, 0x6A) // tag 13: stage_info
+	body = appendUvarint(body, uint64(len(stageBuf)))
+	body = append(body, stageBuf...)
 
 	return s.SendRaw(&NetPacket{CmdType: 1787, Body: body})
 }
@@ -731,6 +803,15 @@ func handleStartChallengeTierce(s *Session, payload []byte) error {
 		}
 	}
 
+	// the 4.6.51 client cannot load arena 3014101 (no MapEntrance) - fall
+	// back to the standard arena, mirroring handleStartChallenge
+	if entrance == 3014101 {
+		entrance = 3000101
+	} else if res, err := common.GameRes(); err == nil && !mapHasEntry(res, entrance) {
+		Log("[CHALLENGE] Tierce arena entrance missing in res.json, fallback to 3000101")
+		entrance = 3000101
+	}
+
 	if player := s.JSON(); player != nil {
 		setChallengeBattleConfig(player, chosenAvatars, req.challengeID, event, buff)
 	}