add dora_ulite6 standalone node with command lifecycle status

Migrates the ulite6 Python dora node from dora_littlehand into a
self-contained repository following the dora-zed structure. Adds
command lifecycle state ("started"/"done"/"failed") and type
("command"/"error") to the status output so coordinator nodes can
reliably sequence robot actions without polling.

dataflow.yml

@@ -0,0 +1,19 @@
+nodes:
+  - id: ulite6
+    git: ssh://git@gitea.liria.cl:5001/liria/dora_ulite6.git
+    git_checkout: v0.1.0
+    build: uv pip install -e .
+    path: dora_ulite6/main.py
+    inputs:
+      tick: dora/timer/millis/10
+    outputs:
+      - status
+      - joint_pose
+      - tcp_pose
+    env:
+      ROBOT_IP: "192.168.1.192"
+      DEFAULT_SPEED: "30"
+      DEFAULT_UNITS: "mm"
+      API_HOST: "0.0.0.0"
+      API_PORT: "9000"
+      VACUUM_ENABLED: "true"