Update README.md

Author: raold

README.md

@@ -32,7 +32,7 @@ This API enables ingestion of text data, which is embedded via OpenAI's `text-em
 
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-![System Architecture - Dark Theme](docs/fc3585e6-dca3-4044-a2a1-b2192fd49eb2.png)
+![System Architecture - Dark Theme](docs/system_architecture.png)
 
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 second-brain/