Remembers the left-margin column for PrintMessage newline (1D) and sub-message (1F) handling.

Working bytes for vocabulary lookup and token walks:

Offset	Holds
ParserState	BASIC/list pointer (BasicHelper)
ParserState_WorkPointer	Work-buffer pointer (SeedPrimaryWorkBuffer)
ParserState_MatchLength	Minimum match length
ParserState_WordIndex	Vocabulary word index
5BA6	Unused
InputBuffer_TokenStart	Current token start (InputBuffer)
InputBuffer_NextToken	Next token start (InputBuffer)
ParserState_TokenChar	First character of token
ParserState_TokenDelimiter	Token delimiter
ParserState_EntryCount	BASIC-list entry count

Line buffer filled by InputLine. Holds up to 3E characters plus a trailing 0D written on Enter.

Working bytes for PrintCharacter / PrintMessage:

Offset	Holds
PrintState	Attribute byte
PrintState_Flags	Flags
PrintState_Column	Column (0-31)
PrintState_Row	Row (0-23)
PrintState_Character	Character code

Working bytes for InputLine:

Offset	Holds
InputLineState	Cursor index into the input buffer
InputLineState_Length	Length of the current input line
InputLineState_LastKey	Previous key (KSTATE)
InputLineState_Dirty	Dirty flag (line changed since last redraw)
InputLineState_SavedLength	Saved length (Caps Shift + 1)