Direct __naked z80 wrappers over BIOS LP_PRINT_*/LP_SET_PLACE/LP_GET_PLACE
(RST 8, opcodes 081h-08Eh) for fast text rendering — a single BIOS call
replaces a wrchar() loop for constant-attribute/constant-character runs.
Covered by tests/bios_text.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
