chore(repo): baseline du fork input-remapper (upstream v2.2.1)

Le dépôt ne contenait que README.md ; ajout de l'intégralité du code
fonctionnel du fork comme socle stable de la branche de release.
L'état runtime d'orchestration (.ideai/) est exclu du suivi.

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

DEBIAN/postinst

@@ -0,0 +1,17 @@
+#!/bin/bash
+if [ -d "/run/systemd/system/" ]; then
+  # old name, those lines should at some point be removed from postinst
+  pkill -f key-mapper-service
+  systemctl disable key-mapper 2> /dev/null || true
+  systemctl stop key-mapper 2> /dev/null || true
+
+  # The ubuntu package creates those two symlinks that break when installing the .deb
+  # built from source. Either ubuntus packages need to be uninstalled with --purge first,
+  # or those files need to be unlinked manually.
+  unlink /etc/systemd/system/input-remapper.service || true
+  unlink /etc/systemd/system/default.target.wants/input-remapper-daemon.service || true
+
+  pkill -f input-remapper-service  # might have been started by the gui previously
+  systemctl enable input-remapper
+  systemctl start input-remapper
+fi