[Mod Manager] - Remake the Mod Manager to be cross-platform and conform to modern standards.

[TopazTK]

NOTE: I am pretty new in MVVM programming and Avalonia, so there may be some unorthodox decisions made within this PR. I will try my best to abide by the feedback I receive and adjust to them as necessary.

What is this PR?

This PR seeks to completely overhaul the Mod Manager and make it fast, user friendly, modern, and cross-platform.

Feature Checklist

General Checklist

• Installation of mods from GitHub.
• Installation of mods from other Git hosts.
• Installation of mods from branches within Git hosts.
• Installation of mods from ZIP Archives.
• Installation of KHPCPatches.
• Installation of standalone Lua files.
• Reordering mod priority and obeying it.
• Removal of mods of all kinds.
• Cancellation and clean-up of mods during installation.
• Ability to navigate to the source folder of mods.
• Mods being marked invalid if they need be.
• Invalid mods being ordered to the bottom priority.
• Construction of metadata for invalid mods.
• Memorization of mod order and activations on a per-game basis.
• Building mods from extracted data. [PC]
• Building mods from game data without prior extraction. [PC]
• Detecting a JP copy and building mods accordingly [PC].
• Building mods from game data without prior extraction. [PCSX2]
• Ability to run games with the launcher [Epic Games Store]
• Ability to run games with the launcher [Steam]
• Ability to run games directly [Steam / Windows]
• Ability to run games directly [Steam / Linux]
• Valid configuration detection and feedback.
• Properly setting mod metadata.
• Properly setting mod source and issues pages if it is a Git mod.
• Properly setting and displaying mod contents.
• Switching games and displaying modlists accordingly.
• Menu bar and its functionality.
• Console output during building mods.
• Error handling during building mods. [Halfway complete but GitHub doesn't have half-check boxes]
• Ability to run games via the Emulator.
• Ability to set Panacea parameters.
• Online Mod Catalog.
• Mod Builder Dialog.

Setup Wizard Checklist:

• Automatic path detection and manual path selection for 1.5+2.5 and 2.8 on Steam [Windows]
• Automatic path detection and manual path selection for 1.5+2.5 and 2.8 on Steam [Linux]
• Automatic path detection and manual path selection for 1.5+2.5 and 2.8 on Epic Games Store
• Manual path selection for emulator.
• Page conditions and blocks according to the chosen platform or current action.
• Panacea installation for 1.5+2.5 and 2.8 on Steam and Epic Games Store [Windows]
• Panacea installation for 1.5+2.5 and 2.8 on Steam Epic Games Store [Linux]
• LuaBackend installation for 1.5+2.5 and 2.8 on Steam and Epic Games Store [Windows]
• LuaBackend installation for 1.5+2.5 and 2.8 on Steam and Epic Games Store [Linux]
• Direct Launch installation and Launch Argument settings for 1.5+2.5 and 2.8 on Steam [Windows]
• Direct Launch installation and Launch Argument settings for 1.5+2.5 and 2.8 on Steam [Linux]
• Ability to extract files from 1.5+2.5 and 2.8 on Steam and Epic Games Store
• Cancellation and invalidation of extraction.
• Ability to extract files from PS2 games.

Panacea-Specific:

• Running built mods for PC.
• Running built mods for emulator

NOTE: There may be some features I have forgotten about. This tool is MASSIVE. Please let me know if there are features missing from the checklist so I can adapt.

Screenshots

Videos

Extractionless Test on Linux:

https://cdn.discordapp.com/attachments/1312193609461796864/1545785001893699766/extractionless-test.mp4?ex=6a9e10b7&is=6a9cbf37&hm=df778106e637b1b92ce761dc9512531950464e3324f2288f183ab34a230c43b1&

Extraction-Based Test on Linux:

https://cdn.discordapp.com/attachments/1312193609461796864/1545785105446863020/extraction-test.mp4?ex=6a9e10d0&is=6a9cbf50&hm=83fe701c820e2df3fede329bd5dbbd0b36892129eed35a5c03f742eaf333e492&

Builds

For the sake of convenience, here are the latest builds for Windows and Linux.
They are Proton Drive links because GitHub is ass.

Latest Windows Build: https://drive.proton.me/urls/5NWPCAQB0R#PJb5kcPimU9u
Latest Linux Build: https://drive.proton.me/urls/VVM02J8DQC#qiVtlFM5PDVc

They are self-contained single-binary builds, as they should be.

Some Notes

I know this isn't as featureful as the AI PR that was closed. I do realize this. But I wanted to prioritize the Desktop builds of the Mod Manager first before dabbling in controller support and touch UI and etc.

I do hope that this PR will be to y'all's satisfaction.

[Vladabdf]

Some recommended additions for QoL:

• Hovering over a mod in the catalog should display an expanded version of its details, in case the name or description are too long
• The user should be able to highlight multiple entries in the mod list at once, to delete en masse or move up/down in priority en masse
• The user should ideally be able to see what makes their mod.yml incompatible, instead of just simply displaying a vague error. This will prevent so many questions, I promise
• In the mod catalog, users should be able to right-click and select "Open mod source", similar to how there is a link after the mod is already installed

To be continued...?

[TopazTK]

Some recommended additions for QoL:

• Hovering over a mod in the catalog should display an expanded version of its details, in case the name or description are too long
• The user should be able to highlight multiple entries in the mod list at once, to delete en masse or move up/down in priority en masse
• The user should ideally be able to see what makes their mod.yml incompatible, instead of just simply displaying a vague error. This will prevent so many questions, I promise
• In the mod catalog, users should be able to right-click and select "Open mod source", similar to how there is a link after the mod is already installed

To be continued...?

• Will be done.
• In the current way things work, scary. I will try though.
• I will get to that. I am trying to format SharpYaml messages a bit better.
• Will be done.

[Vladabdf]

* Will be done.

* In the current way things work, scary. I will try though.

* I will get to that. I am trying to format SharpYaml messages a bit better.

* Will be done.

The second one is the least important, as long as user-made mod presets also stick around :^)

[TopazTK]

* Will be done.

* In the current way things work, scary. I will try though.

* I will get to that. I am trying to format SharpYaml messages a bit better.

* Will be done.

The second one is the least important, as long as user-made mod presets also stick around :^)

The current objective is to have a rate of functionality that is equal to or better than what we currently have.

[sonarqubecloud]

Quality Gate failed

Failed conditions
3.1% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud