docs: document the code generation scripts

[pfeerick]

Summary

Three scripts in the tree generate source files that are committed to git, and the build never runs them. Two of the three were completely undocumented — no mention in docs/, any workflow, or a README:

Generator	Produces
radio/src/fonts/lvgl/make_fonts.sh	radio/src/fonts/lvgl/{std,sml,lrg}/lv_font_*.c
tools/cfn_sorter.sh	radio/src/cfn_sort.cpp
tools/generate-yaml.sh	radio/src/storage/yaml/yaml_datastructs_*.cpp

So there was no way to discover that editing radio/src/translations/i18n/*.h requires re-running two of them, or that their output is committed rather than built.

Adds a Code Generation page covering all three — inputs, prerequisites, and the dev container invocation — and cross-links it from the existing YAML parser page.

The page is deliberately precise about when each generator actually needs re-running, since both translation-driven ones are narrower than they look:

• cfn_sorter.cpp reads only the 25 TR_SF_* special function names, so editing any other translated string leaves cfn_sort.cpp untouched.
• The fonts only change if a translation introduces a character the font does not already contain, and only for cn/tw/jp/he/ko/ru/ua — Latin-script translations never affect them.

Both were verified by editing a string of each kind and re-running the generator.

Second commit

docs/building/windows.md pinned Qt 6.9.0 in three places (the QT_DIR path, the prose, and the aqt install-qt command). CI builds Companion for Windows against 6.9.3 — the qt-version default in .github/actions/build_companion/action.yml, which no workflow overrides — as do the Linux setup scripts and the dev container image. Updated to match.

Note

The new page mentions that tools/setup_buildenv_ubuntu*.sh install the required locales, which is true as of #7603. If this merges first, that one sentence is briefly ahead of reality.

Testing

mkdocs build --strict passes, which is what CI runs. No orphaned pages and no broken nav entries.

🤖 Generated with Claude Code