feat: redesign installer on MTK toolkit with component selection

Rewrite the Installer app on the Montauk Toolkit (Canvas + gui/mtk
widgets, theme, hover states, scrollbar) replacing the hand-rolled px_*
renderer and bespoke TrueType usage.

Add a new "Software" step: an expandable checkbox tree for optional
components (Montauk SDK with gcc/g++, binutils, tcc, lua sub-items;
Games; Office; Internet apps; Printing; experimental httpd and SDR).
Unchecked components' paths are excluded from the install copy, with a
longest-path ownership rule so e.g. sdk/tcc installs even when the rest
of the SDK is deselected. The update flow refreshes only the components
the target already has.

Add tri-state checkbox and disclosure-arrow widgets to the MTK toolkit
(anti-aliased, supersampled).

Merge tcc and lua into 0:/sdk (0:/sdk/tcc, 0:/sdk/lua) and drop 0:/lib:
update tcc config.h, lua luaconf.h, both Makefiles, the devkit clean
scope, man pages and montaukos.org notices.

Make printing optional: init skips printd when 0:/os/printd.elf is
absent.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

programs/src/tcc/Makefile

@@ -89,7 +89,7 @@ TARGET := $(BINDIR)/tcc.elf
 # ---- CRT objects (staged from shared libc) ----
 
 SHARED_CRT_DIR := $(LIBDIR)/libc
-CRT_DIR := ../../bin/lib/tcc/lib
+CRT_DIR := ../../bin/sdk/tcc/lib
 CRT_OBJS := $(CRT_DIR)/crt1.o $(CRT_DIR)/crti.o $(CRT_DIR)/crtn.o
 
 # ---- Rules ----

programs/src/tcc/config.h

@@ -16,10 +16,10 @@
 #undef CONFIG_TCC_BCHECK
 
 /* Paths on MontaukOS ramdisk */
-#define CONFIG_TCCDIR "0:/lib/tcc"
-#define CONFIG_TCC_SYSINCLUDEPATHS "0:/lib/tcc/include"
-#define CONFIG_TCC_LIBPATHS "0:/lib/tcc/lib"
-#define CONFIG_TCC_CRTPREFIX "0:/lib/tcc/lib"
+#define CONFIG_TCCDIR "0:/sdk/tcc"
+#define CONFIG_TCC_SYSINCLUDEPATHS "0:/sdk/tcc/include"
+#define CONFIG_TCC_LIBPATHS "0:/sdk/tcc/lib"
+#define CONFIG_TCC_CRTPREFIX "0:/sdk/tcc/lib"
 #define CONFIG_TCC_ELFINTERP ""
 
 /* We are not native -- no -run support */