fix(aidd-context): correct hooks.json format for Claude Code and Copilot

Was using custom array format — correct format is object map keyed by event name.
Use ${CLAUDE_PLUGIN_ROOT} (supported by both Claude Code and Copilot) to reference the hook script.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: blafourcade

plugins/aidd-context/hooks/hooks.json

@@ -1,10 +1,14 @@
 {
-  "hooks": [
-    {
-      "event": "SessionStart",
-      "matcher": "startup|resume",
-      "command": "node",
-      "args": ["./hooks/update_memory.js"]
-    }
-  ]
+  "hooks": {
+    "SessionStart": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "node ${CLAUDE_PLUGIN_ROOT}/hooks/update_memory.js"
+          }
+        ]
+      }
+    ]
+  }
 }