feat(sync): add SSE live feed, unified logs page, fix Oracle connection

- Add SSE event bus in sync_service (subscribe/unsubscribe/_emit)
- Add GET /api/sync/stream SSE endpoint for real-time sync progress
- Rewrite logs.html: unified runs table + live feed + summary + filters
- Rewrite logs.js: SSE EventSource client, run selection, pagination
- Dashboard: clickable runs navigate to /logs?run=, sync started banner
- Remove "Import Comenzi" nav item, delete sync_detail.html
- Add error_message column to sync_runs table with migration
- Fix: export TNS_ADMIN as OS env var so oracledb finds tnsnames.ora
- Fix: use get_oracle_connection() instead of direct pool.acquire()
- Fix: CRM_POLITICI_PRET_ART INSERT to match actual table schema

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

api/app/templates/dashboard.html

@@ -105,6 +105,11 @@
                 <small class="text-muted" id="syncProgressText"></small>
             </div>
         </div>
+        <div class="mt-2 d-none" id="syncStartedBanner">
+            <div class="alert alert-info alert-sm py-1 px-2 mb-0 d-inline-block">
+                <small><i class="bi bi-broadcast"></i> Sync pornit — <a href="#" id="syncRunLink">vezi progresul live</a></small>
+            </div>
+        </div>
     </div>
 </div>