feat: add neovim text editor

docs(changelog): finalize v1.1.1 release notes

feat(embedded): add ARM Cortex-A Linux cross-compiler for STM32MP135F

Add gcc-arm-linux-gnueabihf and libc6-dev-armhf-cross to both Dockerfiles
for cross-compiling Linux userspace applications targeting STM32MP135F
(Cortex-A7). Update README with embedded board support table and component
source tables. Update USER_GUIDE §0.4 and §13.7 with both board workflows.

docs: add CI verification results for v1.0.0 release

Both GitHub Actions workflows (build + publish) verified via v1.0.0-rc1
pre-release. Updated CHANGELOG and USER_GUIDE testing status.

docs(changelog): finalize v1.0.0 release notes

Add 1.0.0 entry with supply chain messaging clarification, Dockerfile
fixes, and verified test results for nerdctl rootless and Docker rootful.
Update USER_GUIDE version to 1.0.0.