Task: Add unique records to Airtable

n8n workflow JSON:
{"nodes":[{"name":"On clicking 'execute'","type":"n8n-nodes-base.manualTrigger","position":[250,300],"parameters":{},"typeVersion":1},{"name":"Airtable","type":"n8n-nodes-base.airtable","position":[500,400],"parameters":{"operation":"list","additionalOptions":{}},"credentials":{"airtableApi":"Airtable Credentials @n8n"},"typeVersion":1},{"name":"Set","type":"n8n-nodes-base.set","position":[500,200],"parameters":{"values":{"number":[],"string":[{"name":"Name","value":"n8n"}]},"options":{},"keepOnlySet":true},"typeVersion":1},{"name":"Merge","type":"n8n-nodes-base.merge","position":[700,300],"parameters":{"mode":"removeKeyMatches","propertyName1":"Name","propertyName2":"fields.Name"},"typeVersion":1},{"name":"Airtable1","type":"n8n-nodes-base.airtable","position":[900,300],"parameters":{"options":{},"operation":"append"},"credentials":{"airtableApi":"Airtable Credentials @n8n"},"typeVersion":1}],"connections":{"Set":{"main":[[{"node":"Merge","type":"main","index":0}]]},"Merge":{"main":[[{"node":"Airtable1","type":"main","index":0}]]},"Airtable":{"main":[[{"node":"Merge","type":"main","index":1}]]},"On clicking 'execute'":{"main":[[{"node":"Set","type":"main","index":0},{"node":"Airtable","type":"main","index":0}]]}}}