Feature | Feature/taskbar flash progress

[AnnaSasDev]

Impact

Medium

Problem / Motivation

No taskbar progress/flash API in public managed interface or native export constants.

Current behavior

Relevant primitives exist in the files listed above, but this backlog item does not have a complete, explicit InfiniFrame contract with dedicated coverage.

Expected behavior

Add Windows-specific taskbar progress/flash API with capability detection; define no-op/throw strategy for unsupported platforms.

Proposed solution

Implement this incrementally:

1. Define/adjust the managed public API in InfiniFrame.Shared.
2. Wire implementation in InfiniFrame and InfiniFrame.Native where required.
3. Add focused tests (tests/InfiniFrameTests*) and docs updates (docs/docs/guides/*, docs/docs/migration/*).

Alternatives considered

• Keep as unsupported and document migration limitation.
• Provide a workaround-only approach without first-class API.

Use case

Applications migrating from Photino expect this behavior and currently need custom handling for "Feature/taskbar flash progress".

Technical proposal

Scope implementation to: native platform layer (src/InfiniFrame.Native/*) plus managed interop (src/InfiniFrame.Shared/Native/*). Keep behavior deterministic across Windows/Linux/macOS and document platform-specific limitations explicitly.

Additional context

Photino reference: tryphotino/photino.Native#168

Checklist

• I searched existing issues
• This is not a support question