Linux Support Part 1

[RyeMutt]

Description

• Reintroduces Linux 64-bit support to the viewer utilizing previous work in archive/develop
• Implements SDL3 window and input for Linux
• Implements SDL3 filepickers for Linux
• Fixes numerous GCC compiler warnings and build errors
• Restores llappearanceutility
• Implements various reductions in build time such as a global precompiled header
• Migrates tut suite to be ran using ctest after all artifacts are built
• Fixes various conditions that trigger a full rebuild under makefile/ninja generators
• Fixes shader cache failing on linux after being cleared
• Fixes water shader being stuck as opaque when reset by feature table
• Fixes GL errors under DebugGL for mesa drivers on linux
• Fixes memory alignment errors reported by asan and ubsan
• Fixes uninitialized memory reads reported by ubsan
• Fixes class and vptr alignment errors reported by asan by modernizing c++ alignment usage
• Add support for building with Undefined, Thread, and Address sanitizers under linux

Related Issues

Issue Link: #1149 #4587

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Checklist

Please ensure the following before requesting review:

• I have provided a clear title and detailed description for this pull request.
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• The PR is linked to a relevant issue with sufficient context.
• I have tested the changes locally and verified they work as intended.
• All new and existing tests pass.
• Code follows the project's style guidelines.
• Documentation has been updated if needed.
• Any dependent changes have been merged and published in downstream modules
• I have reviewed the contributing guidelines.

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Additional Notes

[RyeMutt]

As this PR has grown rather large I'm going to land the rest of the changes in a follow up PR.

[FelixWolf]

Builds cleanly for me, no warnings.
Experienced no issues with it running either.

[Geenz]

Going ahead and merging this into develop-linux - we're gonna use that as a staging ground for Linux support before we merge it into develop proper. Especially since part 2 of this has a good bit of GL refactoring to go along side of this.