Add property-based mount animation discovery and procedural lean

Mount Animation System:
- Property-based jump animation discovery using sequence metadata
- Chain linkage scoring (nextAnimation/aliasNext) for accurate detection
- Correct loop detection: flags & 0x01 == 0 means looping
- Avoids brake/stop animations via blendTime penalties
- Works on any mount model without hardcoded animation IDs

Mount Physics:
- Physics-based jump height: vz = sqrt(2 * g * h)
- Configurable MOUNT_JUMP_HEIGHT constant (1.0m default)
- Procedural lean into turns for ground mounts
- Smooth roll based on turn rate (±14° max, 6x/sec blend)

Audio Improvements:
- State-machine driven mount sounds (jump, land, rear-up)
- Semantic sound methods (no animation ID dependencies)
- Debug logging for missing sound files

Bug Fixes:
- Fixed mount animation sequencing (JumpStart → JumpLoop → JumpEnd)
- Fixed animation loop flag interpretation (0x20 vs 0x21)
- Rider bone attachment working correctly during all mount actions

include/game/opcodes.hpp

@@ -42,6 +42,7 @@ enum class Opcode : uint16_t {
     SMSG_CHAR_DELETE                 = 0x03C,
     SMSG_PONG                        = 0x1DD,
     SMSG_LOGIN_VERIFY_WORLD          = 0x236,
+    SMSG_LOGIN_SETTIMESPEED          = 0x042,
     SMSG_ACCOUNT_DATA_TIMES          = 0x209,
     SMSG_FEATURE_SYSTEM_STATUS       = 0x3ED,
     SMSG_MOTD                        = 0x33D,