refactor: cleanup serialization effort

+semver: minor

Author: mrdav30

.editorconfig

@@ -0,0 +1,3 @@
+root = true
+[*]
+end_of_line = lf

AGENTS.md

@@ -1,12 +1,14 @@
 # FixedMathSharp agent instructions
 
 ## Project intent and architecture
+
 - This repository is a deterministic fixed-point math library centered on `Fixed64` (`src/FixedMathSharp/Numerics/Fixed64.cs`) with Q32.32 representation (`SHIFT_AMOUNT_I = 32` in `src/FixedMathSharp/Core/FixedMath.cs`).
 - Most API surface lives in value-type numerics (`Fixed64`, `Vector2d`, `Vector3d`, `FixedQuaternion`, `Fixed3x3`, `Fixed4x4`) plus bounds types (`BoundingBox`, `BoundingSphere`, `BoundingArea`) implementing `IBound`.
 - Keep operations deterministic and allocation-light; many methods use `m_rawValue` and `[MethodImpl(MethodImplOptions.AggressiveInlining)]` for hot paths.
 - `FixedMath` and `FixedTrigonometry` are the shared algorithm backbones; extension classes in `src/FixedMathSharp/Numerics/Extensions/` are thin forwarding wrappers, not alternate implementations.
 
 ## Build and test workflows
+
 - Solution: `FixedMathSharp.sln` with library project and test project.
 - Target frameworks are configured in the respective `.csproj` files; `net8.0` is the primary TFM.
 - Typical local workflow:
@@ -19,6 +21,7 @@
 - Packaging/versioning comes from `src/FixedMathSharp/FixedMathSharp.csproj`: GitVersion variables are consumed when present, otherwise version falls back to `0.0.0`.
 
 ## Code conventions specific to this repo
+
 - Prefer `Fixed64` constants (`Fixed64.Zero`, `Fixed64.One`, `FixedMath.PI`) over primitive literals in math-heavy code.
 - Preserve saturating/guarded semantics in operators and math helpers (for example `Fixed64` add/sub overflow behavior).
 - When touching bounds logic, maintain cross-type dispatch shape in `Intersects(IBound)` and shared clamping projection via `IBoundExtensions.ProjectPointWithinBounds`.
@@ -28,11 +31,14 @@
 - `ThreadLocalRandom` is marked `[Obsolete]`; new deterministic RNG work should prefer `DeterministicRandom` and `DeterministicRandom.FromWorldFeature(...)` in `src/FixedMathSharp/Utility/DeterministicRandom.cs`.
 
 ## Testing patterns to mirror
+
 - Tests are xUnit (`tests/FixedMathSharp.Tests`). Keep one feature area per test file (e.g., `Vector3d.Tests.cs`, `Bounds/BoundingBox.Tests.cs`).
 - Use helper assertions from `tests/FixedMathSharp.Tests/Support/FixedMathTestHelper.cs` for tolerance/range checks rather than ad-hoc epsilon logic.
 - For deterministic RNG changes, validate same-seed reproducibility and bounds/argument exceptions like in `DeterministicRandom.Tests.cs`.
 
 ## Agent editing guidance
+
 - Keep public API shape stable unless the task explicitly requests API changes.
 - Match existing style (regions, XML docs, explicit namespaces, no implicit usings).
-- Make focused edits in the relevant numeric/bounds module and update corresponding tests in the parallel test file.
+- Make focused edits in the relevant numeric/bounds module and update corresponding tests in the parallel test file.
+- For serialization changes, ensure MemoryPack attributes are correctly applied and roundtrip tests are updated.