feat(plugin): after-write hook — PostToolUse on Bash diffs the working tree and runs the prior-art + ledger arms on what was just written; shared scribe_defs.sh; plugin 0.1.39 (#2901, milestone 299 step 3)

Edits made through sed/heredocs/scripts never reached the PreToolUse
Write|Edit hook, so a whole class of writes got no prior-art hint, no
ledger feed and no duplicate-family warning. scribe_after_write.sh asks git
what changed since it last looked (per-session path+blob snapshot; first
call = files touched in the last minute), extracts the definitions in the
added lines and calls /api/plugin/prior-art with the same three dedup
channels the pre hook keeps. Never blocks; silent on any failure. The
extractor, the prose/data skip list and the local by-name arm move to
scribe_defs.sh, sourced by both hooks. Version bump covers the step-2 hook
change too (run 4239 failed only on the bump check).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

plugin/hooks/hooks.json

@@ -34,6 +34,17 @@
           }
         ]
       }
+    ],
+    "PostToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "bash \"${CLAUDE_PLUGIN_ROOT}/hooks/scribe_after_write.sh\""
+          }
+        ]
+      }
     ]
   }
 }