feat(metacognitive-guard): add session observer Stop hook (sync prompt) (#142)

Test hook: haiku observes every response and outputs a session progress
summary via additionalContext. Validates whether sync prompt hooks on
Stop events provide human-visible session tracking.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: ANcpLua

plugins/metacognitive-guard/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "metacognitive-guard",
   "description": "Cognitive amplification stack: epistemic hooks, competitive review, commit integrity checks, CI verification scripts, and deep-thinking agents.",
-  "version": "0.4.1",
+  "version": "0.4.3",
   "author": {
     "name": "AncpLua",
     "url": "https://github.com/ANcpLua"

plugins/metacognitive-guard/hooks/hooks.json

@@ -59,6 +59,17 @@
             "statusMessage": "Evaluating response quality..."
           }
         ]
+      },
+      {
+        "hooks": [
+          {
+            "type": "prompt",
+            "model": "haiku",
+            "prompt": "You are a silent session observer. You see Claude's latest response. Extract what was just accomplished and what appears to remain. Output ONLY: {\"hookSpecificOutput\":{\"hookEventName\":\"Stop\",\"additionalContext\":\"SESSION: [done] → [in progress] → [remaining]\"}}. Keep it under 30 words. If the response is trivial (greeting, short answer), return {}.",
+            "timeout": 10,
+            "statusMessage": "Session observer..."
+          }
+        ]
       }
     ],
     "PostToolUse": [