⚡ Bolt: 🔒 Explicitly null-terminate ltsymbol after strncpy (#9)

* Explicitly null-terminate ltsymbol after strncpy

Added explicit null-termination for `ltsymbol` in `arrangemon`, `createmon`,
and `setlayout` to fix potential buffer over-reads.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

* Replace strncpy with snprintf for ltsymbol

Replaced `strncpy` with `snprintf` when assigning `ltsymbol` in
`arrangemon`, `createmon`, and `setlayout` to guarantee null-termination
and fix potential buffer over-reads.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

---------

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

Author: CasperGamingOne

dwm.c

@@ -398,7 +398,7 @@ arrange(Monitor *m)
 void
 arrangemon(Monitor *m)
 {
-	strncpy(m->ltsymbol, m->lt[m->sellt]->symbol, sizeof m->ltsymbol);
+	snprintf(m->ltsymbol, sizeof m->ltsymbol, "%s", m->lt[m->sellt]->symbol);
 	if (m->lt[m->sellt]->arrange)
 		m->lt[m->sellt]->arrange(m);
 }
@@ -645,7 +645,7 @@ createmon(void)
 	m->topbar = topbar;
 	m->lt[0] = &layouts[0];
 	m->lt[1] = &layouts[1 % LENGTH(layouts)];
-	strncpy(m->ltsymbol, layouts[0].symbol, sizeof m->ltsymbol);
+	snprintf(m->ltsymbol, sizeof m->ltsymbol, "%s", layouts[0].symbol);
 	return m;
 }
 
@@ -1538,7 +1538,7 @@ setlayout(const Arg *arg)
 		selmon->sellt ^= 1;
 	if (arg && arg->v)
 		selmon->lt[selmon->sellt] = (Layout *)arg->v;
-	strncpy(selmon->ltsymbol, selmon->lt[selmon->sellt]->symbol, sizeof selmon->ltsymbol);
+	snprintf(selmon->ltsymbol, sizeof selmon->ltsymbol, "%s", selmon->lt[selmon->sellt]->symbol);
 	if (selmon->sel)
 		arrange(selmon);
 	else