lua plugin remove strfrtime in favor of strfrtm.lua

saves 2.2k on the bin

also supplies gmtime, and a test script to check the returned time/dates

Change-Id: Ib83b11d89bdf44a50830ff51c72ac6395b675603

apps/plugins/lua_scripts/time_date.lua

@@ -0,0 +1,48 @@
+--[[
+             __________               __   ___.
+   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+                     \/            \/     \/    \/            \/
+ $Id$
+
+ Copyright (C) 2026 William Wilgus
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+ This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ KIND, either express or implied.
+]]--
+
+if not os.time() then rb.splash(rb.HZ, "No Support!") return nil end
+
+if not os.date() then
+    require("strftime") -- needed for os.time..
+end
+
+local tmo_noblock = -1
+local ctx = 0 --CONTEXT_STD
+
+while rb.get_action(ctx, 50) == 0 do
+    rb.splash(0, os.date())
+end
+
+collectgarbage("collect")
+
+local used, allocd, free = rb.mem_stats()
+local lu = collectgarbage("count")
+local fmt = function(t, v) return string.format("%s: %d b\n", t, v) end
+
+-- this is how lua recommends to concat strings rather than ..
+local s_t = {}
+s_t[1] = os.date()
+s_t[2] = "\n"
+s_t[3] = fmt("Used  ", used)
+s_t[4] = fmt("Allocd ", allocd)
+s_t[5] = fmt("Free  ", free)
+s_t[6] = "\nlua:\n"
+s_t[7] = fmt("Used", lu * 1024)
+s_t[8] = "\n\nNote that the rockbox used count is a high watermark\n"
+rb.splash_scroller(10 * rb.HZ, table.concat(s_t))