[EPIC] Swift Package skeleton

[kirich1409]

Context

Bootstrap Package.swift with four targets (DevsweepCore, DevsweepCorePrivate, DevsweepModules, devsweep CLI) and the correct dependency direction. Establishes the architectural boundary enforcement (S1, S8) at package level so modules cannot import destructive APIs.

Goals

• Package.swift compiles empty targets.
• swift build / swift test green on macOS 14+.
• Dependency graph validated by build: DevsweepModules cannot import DevsweepCorePrivate.

Child tasks

Will be added as sub-issues after task batch.

Exit criteria

• All child tasks closed.
• swift build --configuration release produces single binary.
• Structure matches Plugin API refined design in research report.

Related documents

• Research report §Plugin API — refined design
• Research report §Safety S1, S8