feat(k-ui): first slice: App trait + run loop, builders (column/row/text/button), flex layout, theme tokens (Whimsy Dark), tiny-skia + fontdue render (Noto Sans Latin subset), keyboard focus ring; tally demo; manifest memory key (pm spawns with it)

Makefile

@@ -54,7 +54,7 @@ kani: kani-types kani-domain kani-kernel
 PROGRAMS = -p init -p echo -p sleep -p snake \
 	-p display-qemu -p input-qemu -p storage-qemu \
 	-p log-server -p permission-manager -p session-server -p smptest -p spawntest -p hello \
-	-p terminal-server -p shell -p cat -p ls -p counter -p gatekeeper -p flaky
+	-p terminal-server -p shell -p cat -p ls -p counter -p gatekeeper -p flaky -p tally
 
 # Programs first: the kernel image packs init and storage (see the
 # adapter's build.rs).