Reorganize repository for unified release

[glopesdev]

Adopt the standardised repository layout described in harp-tech/protocol#145, aligning this repository with the conventions shared by other Harp components and enabling a unified release of firmware, software, and documentation from a single CI pipeline.

Repository layout and build infrastructure

• Rename top-level folders to the agreed lowercase layout. The Firmware folder becomes firmware, Hardware becomes hardware, and Interface becomes software. A new docs/ folder is introduced as the root for repository documentation and assets.
• Add shared build infrastructure under software/build/, including Common.csproj.props, Common.csproj.targets, and Package.props, for consistent project metadata and packaging across software components.
• Extend the CI workflow with stages for building the firmware, software, and documentation, rendering workflow images, and publishing packages and documentation as part of a single release.

Self-contained documentation website

Add documentation scaffolding under docs/, including docfx.json, template, articles, images, and workflows. The shared harp-tech/docfx-tools repository is included as the docs/harp-docfx submodule. The site is built from the API metadata of the software components and published from the same CI pipeline that produces the firmware and software releases.

Cross-platform App packaging

Replace the platform-specific NSIS installer with a cross-platform dotnet tool package for the GUI App, installable on any platform with the .NET SDK and launchable as harp.behavior.

Notes

After merging, contributors will need to run git submodule update --init --recursive and dotnet tool restore when checking out the repository.