v0.2.0: add message operation, role filter, showTools, full session IDs

- Add message operation to retrieve a single message by ID (cleaner output,
  higher default maxLength of 8000)
- Add role filter to messages operation (user/assistant/system)
- Hide tool-call parts by default in messages/message output; showTools:true
  to include them
- Show full session IDs instead of truncating to 12 chars
- Make per-message maxLength configurable (default 2000 for messages, 8000
  for message)
- Increase search snippet length from 300 to 500 chars
- Add local development & testing docs to AGENTS.md with symlink instructions
- Bump version from 0.1.0 to 0.2.0

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@alkdev/open-memory",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "description": "OpenCode plugin for session memory browsing, context awareness, and compaction management.",
   "type": "module",
   "main": "dist/index.js",