docs: add episodic-memory to plugins (#203)

Co-authored-by: robertn702 <[email protected]>

data/plugins/episodic-memory.yaml

@@ -0,0 +1,9 @@
+name: Episodic Memory
+repo: https://github.com/robertn702/opencode-episodic-memory
+tagline: Semantic search over your past conversations — local embeddings, no cloud
+description: Indexes your OpenCode session history into a local SQLite store and lets the agent recall past discussions, decisions, and patterns via native episodic_search/episodic_read tools. Fully local and offline — embeddings run in-process via Transformers.js (Snowflake arctic-embed, model chosen by empirical eval), with vector, BM25, and hybrid RRF search modes. Auto-reindexes on session idle; opt-out marker for sensitive chats. Inspired by obra/episodic-memory for Claude Code, rebuilt natively for OpenCode primitives.
+tags:
+  - memory
+  - semantic-search
+  - embeddings
+  - local-first