Explore raw input handling for vendor-specific mouse buttons

[suspiriaa]

Summary

Investigate a lower-level input path for extra mouse buttons that do not appear through the current standard event flow.

Motivation

Some vendor-specific mouse buttons are not exposed through the current input stack, which limits automation coverage for certain devices.

Scope

• research Windows raw input options for extra mouse buttons
• compare raw input behavior with the current backend approach
• document technical tradeoffs and limitations
• if practical, add an experimental implementation behind the Windows backend

Acceptance Criteria

• the repository documents what was tested and what was learned
• the project has a clear next step for vendor-specific mouse input support
• any prototype remains stable for standard mouse input