nx_color.nx

nx_color.nx -- ANSI terminal color escape sequences. Compiler error rendering, log output, debugger UI all benefit from terminal colors when stderr is a TTY. This module exposes the standard ANSI SGR (Select Graphic Rendition) escapes as pre-built byte sequences that callers can write directly. Convention: callers should detect TTY-ness once at startup (typically via isatty(2) or its sim equivalent) and gate color output on that. This module doesn't decide; it just provides the escapes. No string literals as constants in NishiLang yet, so we expose pointer-returning helpers that build the sequences in mmap'd memory (lazy-init, single allocation per sequence). Standard ANSI SGR escape pattern: ESC [ N m ESC = 0x1B = '\e' [ = 0x5B N = digit code (e.g. 31 = red) m = 0x6D We produce the literal byte sequence per code (saves a snprintf- equivalent which we don't have natively yet). nx_safety_envelope: intended_use: "Color primitives (RGB / HSL / Q14 lerp) -- substrate visual pipeline foundation" sil_target: SIL1 asil_target: QM dal_target: NONE evidence: [Q14_fixed_point_color_arithmetic, no_FP, sRGB_canonical_basis] hazard_register: [bug-tape-gamma-uncorrected-output, bug-tape-channel-overflow-via-saturation] residual_risk: "Linear-light vs sRGB gamma is caller- decided; substrate provides both paths." verdict: NOT_YET_EVALUATED