FABRIC.md item 4.5d: GCC's -O2 folds putchar(c)/fputc(c,stdout) call sites
into putc(c,stdout), and getchar() into getc(stdin) -- neither symbol was
ever needed at -O0 because that fold pass is inactive there. Both are thin
wrappers reusing the existing putchar()/getchar() implementations exactly
(putc -> console_putc via putchar; getc -> the existing "no stdin in
kernel" -1/EOF stub via getchar), not new behavior.
Harmless at the current -O0 build (nothing calls these symbols directly at
-O0); this is prep for enabling optimization, verified against a clean
amd64 boot at unchanged -O0.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
shim.c — host-service shim bridging the kernel VM subsystem to
src/starkernel/hal/host_services.c, narrowing the interface the VM
core needs from the underlying hardware/firmware layer.
