Add minimal CP/M 2.2 BIOS implementation and BDOS support

[ericTheEchidna]

• Introduced a basic BIOS for the emulator, providing console I/O and stubs for disk routines.
• Implemented a jump table for standard CP/M functions.
• Added necessary data structures and constants for BIOS operations.
• Created a new BDOS symbol file with function addresses and constants.
• Updated CCP symbol file with relevant constants and addresses.

[Copilot]

Pull request overview

This PR introduces a minimal CP/M 2.2 BIOS implementation and BDOS support for the emulator, establishing a fixed memory layout with BDOS at 0xE000, CCP at 0xE900, and BIOS at 0xF200.

• Replaced dynamic origin calculations with explicit address constants for predictable CP/M memory layout
• Converted assembly syntax from 8080 mnemonics to Z80 equivalents throughout CCP and BDOS modules
• Created a minimal BIOS with console I/O via port 0 and stub disk routines that return success without actual disk operations

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
bios.asm	New minimal BIOS implementation with console I/O, disk stubs, and jump table at 0xF200
bios.sym	Symbol file for BIOS entry points and data addresses
bdos.asm	Converted to Z80 syntax and fixed BDOS address at 0xE000, removed conditional ORG logic
bdos.sym	Symbol file with BDOS function addresses and constants
ccp.asm	Converted to Z80 syntax and fixed CCP address at 0xE900, removed origin calculation
ccp.sym	Symbol file with CCP addresses and constants

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[Copilot]

Inconsistent comment style: "EQU" is used instead of "set" in comments. Lines 52-54 use "EQU" (uppercase) in comments like ";EQU track function" which is confusing since EQU is an assembler directive. These should be ";set track function" or ";settrkf function" to match the naming convention.

Suggested change

	settrkf equ bios+3*10 ;EQU track function
	setsecf equ bios+3*11 ;EQU sector function
	setdmaf equ bios+3*12 ;EQU dma function
	settrkf equ bios+3*10 ;set track function
	setsecf equ bios+3*11 ;set sector function
	setdmaf equ bios+3*12 ;set dma function

[Copilot]

Missing space after "equ" directive. The line should be bios equ 0C000h ;next module (with a tab before the comment) to match the spacing convention used elsewhere in the file.

Suggested change

	bios equ 0C000h;next module
	bios equ 0C000h ;next module