Introduce a compile-time out-of-core storage capability for simplnx: a
DataStore abstraction that can back arrays on disk, an IO/recovery path
that registers and finalizes those stores, a memory-budget manager that
decides in-core vs OOC placement, and chunk-aware parallel dispatch so
algorithms stream chunked data efficiently. OOC is gated behind the
compile-time SIMPLNX_USE_OOC switch and is wholly absent from in-core
builds. Every OOC entry point is a direct SimplnxOoc:: function call
guarded by #ifdef SIMPLNX_USE_OOC and compiled into libsimplnx -- there
is no runtime hook, function pointer, or plugin indirection.
93 files changed, +5501 / -1229 lines.

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1. Compile-time OOC switch and SimplnxOoc integration
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Files: CMakeLists.txt, cmake/SimplnxConfig.hpp.in

Add the SIMPLNX_USE_OOC option and a generated SimplnxConfig.hpp that
carries the macro through simplnx's PUBLIC include path, so the value is
identical (ODR-safe) across every consumer and MOC. When enabled, the
private SimplnxOoc sources are compiled in place into libsimplnx -- no
copy into the build tree, no separate library, no simplnx->SimplnxOoc
link cycle -- and a source-dir guard fails configuration if the path is
missing. simplnx core calls SimplnxOoc:: functions directly, all behind
#ifdef SIMPLNX_USE_OOC.

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2. DataStore layer: in-core / out-of-core abstraction
================================================================================
Files: src/simplnx/DataStructure/{AbstractDataStore,DataStore,EmptyDataStore}.hpp,
       src/simplnx/DataStructure/EmptyStringStore.hpp,
       src/simplnx/Utilities/{DataStoreUtilities,ArrayCreationUtilities}.hpp

Generalize the data-store interface so an array can be backed in core or
out of core. Array creation resolves its storage format with a direct,
compile-time-gated SimplnxOoc::resolveFormat call and builds a chunked
store via SimplnxOoc::createChunkedStore / createChunkedListStore when the
OOC format is requested; in-core builds compile none of these calls and
stay fully in core. Add an empty string store and extend the empty data
store for the deferred-load case.

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3. IO collection, format registration, and recovery write
================================================================================
Files: src/simplnx/DataStructure/IO/Generic/DataIOCollection.{hpp,cpp},
       src/simplnx/DataStructure/IO/HDF5/{DatasetIO,NeighborListIO,DataStructureWriter}.*

The DataIOCollection constructor calls SimplnxOoc::registerIOManager to
add the OOC IO manager, and finalizes stores on write via
SimplnxOoc::finalizeStores -- replacing the former plugin's load-time
setup with direct calls. The HDF5 writer calls
SimplnxOoc::maybeWriteRecoveryArray directly so dirty OOC arrays are
flushed during WriteFile.

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4. DREAM3D file loading API and deferred load
================================================================================
Files: src/simplnx/Utilities/Parsing/DREAM3D/Dream3dIO.{hpp,cpp},
       test/Dream3dLoadingApiTest.cpp, test/IOFormat.cpp

Rework the .dream3d loader API. In OOC builds, import is deferred via a
direct SimplnxOoc::handleImport call (lazy load) and writes run under a
SimplnxOoc::RecoveryWriteGuard; in-core builds load eagerly. Migrate the
compression test cases to the new loader API and add coverage for the
loading paths.

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5. Memory budget management and the nxrunner --memory-budget flag
================================================================================
Files: src/simplnx/Utilities/MemoryBudgetManager.{hpp,cpp},
       src/simplnx/Core/Preferences.{hpp,cpp}, src/nxrunner/src,
       test/MemoryBudgetManagerTest.cpp

Add a MemoryBudgetManager that tracks the budget governing in-core vs OOC
placement. Preferences seeds the OOC base directory (via a direct
SimplnxOoc::setBaseDirectory call) and default format on startup and gains
a removeValue helper. nxrunner exposes a --memory-budget flag wired through
to the budget manager, with parsing hardened against NaN, inf, and
trailing garbage.

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6. Chunk-aware parallel dispatch and the Extent utility
================================================================================
Files: src/simplnx/Utilities/AlgorithmDispatch.hpp, src/simplnx/Common/Extent.hpp,
       test/{IParallelAlgorithmTest,ExtentTest}.cpp

Extend algorithm dispatch with direct vs scanline paths so chunked OOC
arrays are traversed in chunk-sequential order rather than thrashing the
cache. Add an Extent helper for region math. Both gain unit tests.

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7. Filter, action, and test updates for OOC
================================================================================
Files: src/Plugins/SimplnxCore/.../Filters (+Algorithms, incl. FillBadData),
       src/simplnx/Filter/Actions, plugin tests, test/UnitTestCommon

Propagate the chosen store format through the data-creation actions and
update the affected SimplnxCore filters/algorithms (notably FillBadData,
reworked to stream Z-slabs via bulk I/O) and OrientationAnalysis/
ITKImageProcessing call sites to the new APIs. Extend UnitTestCommon and
plugin tests accordingly.

Verified: the full OOC-Release build (libsimplnx with the SimplnxOoc
sources compiled in place, all plugins, and all test executables) compiles
and links cleanly; InCore-Release (SIMPLNX_USE_OOC=OFF) builds and the
DREAM3D-NX app launches. The ctest suite was not run.

Signed-off-by: Joey Kleingers <joey.kleingers@bluequartz.net>