F8.2b: Make Aseprite import context-aware

[Flow-Fly]

Parent

• F8.2 — OS file-handler registration for .pf / .aseprite #123

Goal

Make Aseprite import target an explicit ProjectContext, then route .ase and .aseprite files through the durable import service as new library projects.

Context

The current Aseprite importer mutates module singleton stores. That would overwrite the active drawing when invoked from an OS file launch.

Risk and routing

Risk: low
Readiness: ready-for-agent

This is a behavior-preserving dependency-injection refactor followed by one new import adapter, with fixture-backed tests.

Acceptance Criteria

• importAseFile writes only to the supplied context.
• The default context remains supported for existing callers during the transition.
• Aseprite import creates a new durable project and uses the source filename as its project name.
• The previously active project remains unchanged.
• Parse/import failures create no library record.

Suggested Files

• src/services/aseprite-service.ts
• src/services/project-file-import.ts
• Aseprite and import-service tests using repository fixtures

Verification

• Focused Vitest coverage with an Aseprite fixture and two project contexts.
• npm run test:run
• npm run build
• git diff --check

Dependencies

• Implement after the import boundary from the previous child issue.

Out of Scope

• Changing Aseprite parsing fidelity.
• Aseprite export changes.

[Flow-Fly]

Agent Assessment

Risk: low
Agent-ready: yes
Routing: ready-for-agent

Evidence:

• The Aseprite importer currently reads only three singleton stores, all available on ProjectContext.
• Repository fixtures and context-isolation tests can prove behavior without changing parser fidelity.

Why this is safe:

• Explicit dependency injection removes hidden global targeting; the parser and export format stay unchanged.

Verification:

• Fixture-backed context-isolation tests, full tests, production build, and diff check.

Human question or blocker:

• None.