initial: multi-memory provider reference

Saved from the fork's patches/multi-memory branch. Contains the refactored
agent/memory_manager.py that supports N memory providers simultaneously.

Not active — stored for future reference.
- agent_memory_manager_patched.py (the refactored version)
- agent_memory_manager_original.py (upstream version for comparison)
- plugin.yaml + README

README.md

@@ -1,3 +1,37 @@
-# hermes-multimemory-plugin
+# Hermes Multi-Memory Plugin
 
-Hermes multi-memory provider plugin — allows running multiple Honcho instances or alternate memory backends simultaneously. Stored for reference; not currently active.
+Reference/save of the multi-memory provider patch from the fork.
+
+**NOT currently installed or active.** The fork's `patches/multi-memory`
+branch refactors `agent/memory_manager.py` to support running multiple
+memory providers (Honcho, Mem0, SuperMemory, RetainDB, etc.) simultaneously
+instead of only one at a time.
+
+## Files
+
+- `agent_memory_manager_patched.py` — The refactored MemoryManager from the
+  `patches/multi-memory` branch. Handles registration, prefetch, sync, tool
+  routing, and lifecycle hooks for N providers.
+- `agent_memory_manager_original.py` — The original upstream
+  `agent/memory_manager.py` for comparison.
+
+## Why saved but not active
+
+This patch fundamentally changes the MemoryManager class in
+`agent/memory_manager.py`. It cannot be monkey-patched as a plugin because:
+
+1. The class is imported and used at module scope in multiple places before
+   any plugin's `register()` function runs.
+2. The refactor is structural (adding provider orchestration, changing method
+   signatures) — not a simple constant override.
+3. Hermes already has a working single-provider system (Honcho).
+
+The code is saved here for reference if the need for multi-memory support
+ever arises.
+
+## Original patch context
+
+- Branch: `patches/multi-memory` in `gortium/hermes-agent`
+- Primary file changed: `agent/memory_manager.py` (+54 lines)
+- Kept Hermes's existing single-provider behavior as the default while
+  providing the orchestration layer for multi-provider setups