Add explicit action items to codegraph_explore output

- Move warnings to TOP of output so Claude sees them first
- If existing implementations found: "STOP: Similar implementations exist!"
- If feature request: "BEFORE PLANNING: Use AskUserQuestion to clarify..."
- Update tool description to emphasize checking existing code first
- Fixes issue where Claude listed questions but never asked them

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@colbymchenry/codegraph",
-  "version": "0.1.6",
+  "version": "0.1.7",
   "description": "A local-first code intelligence system that builds a semantic knowledge graph from any codebase",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",