🔨[Feature Request] Implementation of Silver Sea Remnants and late ToAU Avatar Quests

[gokudr]

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Describe the feature

Hello! I am requesting the implementation of a few major pieces of Treasures of Aht Urhgan content that currently appear to be missing from the database and scripts:

1. Silver Sea Remnants (Salvage)
Currently, Silver_Sea_Remnants is completely unpopulated in mob_spawn_points. The doors have no scripts attached, and the boss/Pathos mechanics are missing.

2. The Rider Cometh & Unwavering Resolve (Avatar Quests)
The quest IDs exist in globals/quests.lua (THE_RIDER_COMETH = 76, UNWAVERING_RESOLVE = 77, A_STYGIAN_PACT = 78), but the actual Lua scripts, BCNM logic (Hazhalm Testing Grounds), and boss AI for Odin Prime and Alexander Prime have not been implemented.

If any developers have partial scripts, packet captures, or are currently working on these, I would love to test them. Thank you for all the hard work on the emulator!