Add in-memory store and filtering engine

[colemancda]

Summary

Adds a pure Swift in-memory store and filtering engine to the CoreModel target, compatible with Embedded Swift and platforms without Foundation.

• Predicate evaluation engine (Predicate/Evaluate.swift): evaluates any FetchRequest.Predicate against a ModelData instance in memory — comparisons (including cross-numeric-type equality and ordering), compound predicates, string operators (BEGINSWITH, ENDSWITH, CONTAINS, IN, LIKE via a pure Swift wildcard matcher, MATCHES where Foundation regex support is available), relationship comparisons (CONTAINS/IN on to-many, identifier equality on to-one, ANY/ALL modifiers), and custom DatabaseFunction expressions.
• FetchRequest in-memory execution (FetchRequestEvaluation.swift): filters by entity and predicate, sorts by sort descriptors (property and function terms, stable identifier tiebreaker), and applies fetch offset/limit. Public filtered(by:) / sorted(by:) helpers on [ModelData].
• InMemoryModelStorage (InMemoryStore.swift): an actor-backed ModelStorage that keeps all objects in memory and evaluates fetch requests with the new engine, validating every operation's entity against a required Model schema. Uses typed throws (CoreModelError) so it also compiles under Embedded Swift, where the untyped-throws protocol conformance is unavailable and the same API is called directly.
• CoreDataModel now reuses the shared engine: the previous internal, Foundation-only duplicate of predicate evaluation and sorting is removed, and the custom-function fetch path in NSManagedObjectContext delegates to the public CoreModel engine.

Testing

• swift test: 93 tests pass, including 25 new tests covering predicate evaluation, sorting, fetch request execution, and the in-memory store (CRUD, batch operations, predicates, custom functions, schema validation).
• swift build (macOS), swift build --swift-sdk wasm, and SWIFT_EMBEDDED=1 swift build --swift-sdk wasm-embedded all succeed.

[github-code-quality]

Code Coverage Overview

Languages: Swift

Swift / code-coverage/llvm-cov

The overall coverage in commit 97f1ff2 in the feature/in-memory-st... branch remains at 96%, unchanged from commit 935299d in the master branch.

Show a code coverage summary of the most impacted files.

File	master 935299d	feature/in-memory-st... 97f1ff2	+/-
Sources/CoreDat...ctContext.swift	97%	97%	0%
Sources/CoreDat...valuation.swift	100%	100%	0%
Sources/CoreMod.../Evaluate.swift	0%	96%	+96%
Sources/CoreMod...moryStore.swift	0%	100%	+100%
Sources/CoreMod...valuation.swift	0%	100%	+100%

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_{Updated July 21, 2026 12:57 UTC}