Agent knowledge hub and deepseek-harness plugin

Key features

• Common Memory Service with provider filters, user routing policies, and provenance.
• The name refers directly to Patchouli Knowledge, and also pays tribute to the widely known Minecraft mod Patchouli.
• Consumer-side aggregation that keeps native plugin results intact, with optional dedicated-model evidence selection.
• Incremental retrieval streams with backpressure and a final complete aggregate.
• Agent Loop connector with configurable hooks and model tools.