htop: enable GPU field (sorta, see note)

hosts/common/programs/htop/default.nix

@@ -1,3 +1,9 @@
+# N.B.(2025-07-23):
+# - gpu stats require `BUNPEN_DISABLE=1`.
+#   these are obtained via /proc/$super/fdinfo;
+#   <https://www.kernel.org/doc/html/latest/gpu/drm-usage-stats.html>
+#   no idea if this is a fundamental thing (drm subsystem is namespace unaware),
+#   or something else.
 { ... }:
 {
   sane.programs.htop = {

hosts/common/programs/htop/htoprc

@@ -1,8 +1,8 @@
 # Beware! This file is rewritten by htop when settings are changed in the interface.
 # The parser is also very primitive, and not human-friendly.
-htop_version=3.3.0
+htop_version=3.4.1
 config_reader_min_version=3
-fields=0 48 6 18 39 130 2 46 47 49 1
+fields=0 48 6 17 18 39 130 2 46 47 49 1
 hide_kernel_threads=1
 hide_userland_threads=0
 hide_running_in_container=0
@@ -27,6 +27,7 @@ show_cpu_usage=1
 show_cpu_frequency=0
 show_cpu_temperature=0
 degree_fahrenheit=0
+show_cached_memory=1
 update_process_names=0
 account_guest_in_cpu_meter=0
 color_scheme=0
@@ -36,8 +37,8 @@ hide_function_bar=0
 header_layout=two_67_33
 column_meters_0=AllCPUs Memory Swap Zram
 column_meter_modes_0=1 1 1 1
-column_meters_1=Systemd Uptime Tasks LoadAverage NetworkIO DiskIO
-column_meter_modes_1=2 2 2 2 2 2
+column_meters_1=Systemd Uptime Tasks LoadAverage Blank GPU NetworkIO DiskIO
+column_meter_modes_1=2 2 2 2 2 2 2 2
 tree_view=0
 sort_key=46
 tree_sort_key=0