Add orionpkg (package manager GUI) + installer locale step

orionpkg/orionpkg.c (~500 lines, native Xlib/Xft):
- Launches with checkupdates (pacman-contrib) to list pending upgrades
- ST_CHECKING: animated spinner while querying
- ST_UPDATES: scrollable package list with name / old ver → new ver columns
- ST_UPDATING: pkexec pacman -Syu in background, live log output,
  progress bar estimated from pacman's (N/M) counters
- ST_DONE / ST_ERROR: success or failure screen
- Refresh (r key), scroll (mouse wheel / arrow keys), Close (Esc/q)
- pacman-contrib added to ISO packages

Installer: add STEP_LOCALE (timezone + keyboard layout):
- Inserted between STEP_DISK and STEP_USER
- Timezone pane: searchable filter input + scrollable list of 37 zones
- Keyboard pane: 20 common layouts with code + description
- Timezone and keyboard passed as args 6/7 to orioninstall
- orioninstall: sets /etc/vconsole.conf and X11 xorg.conf.d keyboard
  config from args; uses selected timezone for localtime symlink

Also:
- Right-click menu: "Software Updates" → orionpkg
- Root Makefile: orionpkg target + install rule
- ISO: orionpkg binary installed, permissions map, gitignore

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

orionpkg/Makefile

@@ -0,0 +1,15 @@
+BIN = orionpkg
+
+CC     = gcc
+CFLAGS = -Wall -Wextra -O2 \
+          $(shell pkg-config --cflags x11 xft fontconfig 2>/dev/null)
+LIBS   = $(shell pkg-config --libs   x11 xft fontconfig 2>/dev/null) \
+          -lX11 -lXft -lfontconfig
+
+$(BIN): orionpkg.c
+	$(CC) $(CFLAGS) -o $@ $< $(LIBS)
+
+clean:
+	rm -f $(BIN)
+
+.PHONY: clean