Add missing var plugin files and update gitignore

- Added var plugin implementation files (get, set, delete, exists)
- Updated .gitignore to not ignore backend/autometabuilder/workflow/plugins/var/
- These files were created but not committed due to gitignore pattern

Co-authored-by: johndoe6345789 <224850594+johndoe6345789@users.noreply.github.com>

.gitignore

@@ -19,6 +19,7 @@ lib64/
 parts/
 sdist/
 var/
+!backend/autometabuilder/workflow/plugins/var/
 wheels/
 share/python-wheels/
 *.egg-info/

backend/autometabuilder/workflow/plugins/var/__init__.py

@@ -0,0 +1 @@
+"""Variable management workflow plugins."""

backend/autometabuilder/workflow/plugins/var/var_delete.py

@@ -0,0 +1,15 @@
+"""Workflow plugin: delete variable from workflow store."""
+
+
+def run(runtime, inputs):
+    """Delete variable from workflow store."""
+    key = inputs.get("key")
+    
+    if key is None:
+        return {"result": False, "deleted": False, "error": "key is required"}
+    
+    if key in runtime.store:
+        del runtime.store[key]
+        return {"result": True, "deleted": True}
+    
+    return {"result": False, "deleted": False}

backend/autometabuilder/workflow/plugins/var/var_exists.py

@@ -0,0 +1,13 @@
+"""Workflow plugin: check if variable exists in workflow store."""
+
+
+def run(runtime, inputs):
+    """Check if variable exists in workflow store."""
+    key = inputs.get("key")
+    
+    if key is None:
+        return {"result": False, "error": "key is required"}
+    
+    exists = key in runtime.store
+    
+    return {"result": exists}

backend/autometabuilder/workflow/plugins/var/var_get.py

@@ -0,0 +1,15 @@
+"""Workflow plugin: get variable from workflow store."""
+
+
+def run(runtime, inputs):
+    """Get variable value from workflow store."""
+    key = inputs.get("key")
+    default = inputs.get("default")
+    
+    if key is None:
+        return {"result": default, "exists": False, "error": "key is required"}
+    
+    exists = key in runtime.store
+    value = runtime.store.get(key, default)
+    
+    return {"result": value, "exists": exists}

backend/autometabuilder/workflow/plugins/var/var_set.py

@@ -0,0 +1,14 @@
+"""Workflow plugin: set variable in workflow store."""
+
+
+def run(runtime, inputs):
+    """Set variable value in workflow store."""
+    key = inputs.get("key")
+    value = inputs.get("value")
+    
+    if key is None:
+        return {"result": None, "key": None, "error": "key is required"}
+    
+    runtime.store[key] = value
+    
+    return {"result": value, "key": key}