Namespaces were shared across features: `settings` was written by core, the
panel and touch, and `input` by touch and buttons. That made "does this
firmware implement the whole feature?" a question no pointer could answer.
Each namespace now belongs to exactly one feature or to core, so a feature is
a provider pointer and the compiler validates completeness:
gui, node -> screen, tree, under the screen feature
settings -> screen (rotation, theme), sys (timezone),
touch (calibration)
input -> touch, buttons
Runtime::open() no longer requires a GuiProvider; a firmware without one runs
with no screen/tree globals and reports sys.hasFeature("screen") false.
Rotation is one value again: GuiProvider::setRotation applies and persists, so
an app rotating the panel transiently puts the old value back itself.
The firmware knew four paths and called four globals, so the card could
not change its own layout or put anything around an app. It now loads one
file, and the table that file returns owns the rest: start() mounts the
route, home and data name the tree, and every callback is a field on it
rather than a global the app and its chrome would have to share.
ui.lua and hints.lua are compiled to LUA_32BITS bytecode (matching the
firmware's Lua build) and linked into the binary. A new package.searchers
entry checks them as the fallback after the SD card, so a local
/.lua/lib/ui.lua still shadows the packaged one for debugging.
Bytecode is ~40% smaller than source and loads without parsing. A fresh
SD card with no make sdcard now has the platform available.