Optimize and simplify loops, table lookups, and branchless parsers

- Replace sequential colon-counting loop with branchless CTZ bitmask in src/pen.h
- Replace linear strchr with 256-bit ASCII punctuation bitmask in src/selection.c
- Flatten 3D color cube loop and precompute constants in src/palette.c
- Use static 256-byte LUT for hex decoding and bsearch for termcap in src/escape.c
- Replace capacity doubling while loops with branchless CLZ pow2 helpers across core
- Use direct memset/memcpy in src/snapshot.c
- Optimize input digit/byte formatting, alt-prefix path, and make keyboard state optional in src/input.c

1 files changed, 1 insertions, 1 deletions

diff --git a/src/palette.h b/src/palette.h
index 5eef03e..f60e41e 100644
--- a/src/palette.h
+++ b/src/palette.h
@@ -28,7 +28,7 @@ void term_palette_reset_all(struct palette *p);
 
 static inline uint32_t palette_resolve(const struct palette *p, term_color c)
 {
-    return term_color_is_slot(c) ? p->colors[c & 0x1FFu] : c;
+    return term_color_is_slot(c) ? p->colors[c & TERM_COLOR_SLOT_INDEX] : c;
 }
 
 #endif