Add mkfile for building all Ollie projects

mkfile

@@ -0,0 +1,32 @@
+# Build all Ollie projects in sequence
+#
+# Usage:
+#   mk            # build everything
+#   mk core       # build only core
+#   mk tui        # build only tui
+#   mk 9p         # build only 9p
+#   mk all        # build everything (default)
+
+all: core tui 9p
+
+core:V:
+	echo === Building ollie-core ===
+	cd core && mk
+
+tui:V:
+	echo === Building ollie-tui ===
+	cd tui && mk
+
+9p:V:
+	echo === Building ollie-9p ===
+	cd 9p && mk
+
+help:V:
+	echo 'Ollie monorepo build targets:'
+	echo '  all     - Build all projects (default)'
+	echo '  core    - Build core library'
+	echo '  tui     - Build terminal UI'
+	echo '  9p      - Build 9p filesystem server'
+	echo ''
+	echo 'Submodules must be initialized first:'
+	echo '  git submodule update --init --recursive'