Add fast-jev-compaction extension — Jev System One compaction hook (session_before_compact): prunes stale tool calls/results, keeps user/assistant text verbatim

extensions/fast-jev-compaction/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "fast-jev-compaction",
+  "version": "1.0.0",
+  "description": "Fast Jev System One context compaction extension for Pi coding agent",
+  "type": "module",
+  "main": "index.ts",
+  "pi": {
+    "extensions": ["./index.ts"]
+  },
+  "dependencies": {},
+  "peerDependencies": {
+    "@earendil-works/pi-agent-core": "*",
+    "@earendil-works/pi-coding-agent": "*"
+  },
+  "devDependencies": {}
+}