fix: Simplify search endpoint parameters to avoid bracket encoding

Replace complex array/object parameters with simple comma-separated strings
and flat date parameters to eliminate annoying URL bracket encoding issues.

Changes:
- Add normalizeParams() helper to convert URL-friendly params to internal format
- Replace obs_type/concepts/files arrays with comma-separated strings
- Replace dateRange object with dateStart/dateEnd scalar params
- Update all tool schemas to use simplified parameters
- Add normalization to all tool handlers

Examples of new simplified URLs:
- Before: ?concepts[]=decision&concepts[]=bugfix&dateRange[start]=2024-01-01
- After: ?concepts=decision,bugfix&dateStart=2024-01-01

All endpoints tested and working correctly.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "claude-mem",
-  "version": "6.0.9",
+  "version": "6.3.6",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "claude-mem",
-      "version": "6.0.9",
+      "version": "6.3.6",
       "license": "AGPL-3.0",
       "dependencies": {
         "@anthropic-ai/claude-agent-sdk": "^0.1.27",