Version 2.4: native DMI and PNG document workflows

[PhantornRU]

Summary

• Add a source-referenced SpriteDocument model for ordered states, 1/4/8 directions, animation metadata, crops, and transforms.
• Add content-aware DMI/PNG probing and PNG single-image, sequence, and sprite-sheet import in a Documents workspace.
• Add schema-v1 sidecar projects with source fingerprints, relative relocation, safety limits, and per-source Accept/Relink/Cancel recovery. Accepted or relinked projects remain dirty until saved.
• Add verified DMI export with invariant animation/hotspot metadata and managed PNG sheet/sequence export with sibling staging and ownership manifests.
• Migrate Workspace settings to v8 and extend batch processing with independent DMI/PNG outputs and raster profiles.

Rationale and impact

V2.3 editor and writer hardening was DMI-specific and could not represent ordinary PNG assets without losing state, direction, or source semantics. V2.4 introduces a document boundary while preserving mapping JSON v2, CSV import, the public IDmiWriter contract, and the existing atomic DMI writer behavior.

Changed or missing sources require an explicit decision before a project replaces the active document. DMI animation delays are normalized independently of the Windows locale. Batch output failures remain isolated per format, and unmanaged raster folders or colliding output paths are rejected without overwriting existing data.

Validation

• Locked restore with .NET SDK 10.0.302
• Debug and Release builds with zero warnings
• 242 unit tests and 77 integration tests
• NuGet transitive vulnerability audit
• Hidden-Unicode and diff checks
• Self-contained win-x64 package, SHA-256, ZIP/sample smoke extraction
• Packaged WPF startup smoke

Manual sign-off remains for 100/125/150% DPI and opening exported DMI in an independent BYOND/DMI tool.