busybox: Raise shell history limit to 16k, default to 1k

The busybox-w32 defconfig caps HISTSIZE at 1023 and defaults to 384,
which is cramped for desktop use. Nothing in the history code is worse
than linear. The one cost that scales with history is fork emulation:
each forkshell child of an interactive shell (command substitution,
subshell, pipeline stage) receives a copy of the in-memory history. At
10k entries that adds roughly 0.3 ms to a ~5 ms spawn. The cap itself
only sizes a fixed pointer array, so raising it is nearly free, and
the 1024 default stays well under 1% per fork.

Upstream Kconfig limits FEATURE_EDITING_HISTORY to 2000, and kconfig
treats out-of-range values as unset, so patch the range.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Dockerfile

@@ -742,6 +742,8 @@ RUN QUILT_PATCHES=$PREFIX/src/busybox quilt push -a \
             -e 's/^# (CONFIG_BASH_IS_NONE) is not set/\1=y/' .config \
  && sed -ri 's/^(CONFIG_CRON\w*)=y/\1=n/' .config \
  && sed -ri 's/^(CONFIG_DPKG\w*)=y/\1=n/' .config \
+ && sed -ri 's/^(CONFIG_FEATURE_EDITING_HISTORY)=.*/\1=16384/' .config \
+ && sed -ri 's/^(CONFIG_FEATURE_EDITING_HISTORY_DEFAULT)=.*/\1=1024/' .config \
  && sed -ri 's/^(CONFIG_FEATURE_FAIL_IF_UTF8_MANIFEST_UNSUPPORTED)=y/\1=n/' .config \
  && sed -ri 's/^(CONFIG_FTP\w*)=y/\1=n/' .config \
  && sed -ri 's/^(CONFIG_LINK)=y/\1=n/' .config \

src/busybox/history-limit.patch

@@ -0,0 +1,11 @@
+--- a/libbb/Config.src
++++ b/libbb/Config.src
+@@ -193,7 +193,7 @@
+ config FEATURE_EDITING_HISTORY
+ 	int "History size"
+ 	# Don't allow way too big values here, code uses fixed "char *history[N]" struct member
+-	range 0 2000
++	range 0 16384
+ 	default 200
+ 	depends on FEATURE_EDITING
+ 	help

src/busybox/series

@@ -4,3 +4,4 @@ default-noiconify.patch
 system-profile.patch
 zstd.patch
 mkdtemp.patch
+history-limit.patch