Critical fix: Add ICE candidate handlers to service pool

The service pool was creating peer connections but never setting up
onicecandidate handlers. This meant ICE candidates generated by the
TURN relay were never sent to the signaling server, causing all
ICE connectivity checks to fail with no remote candidates.

Changes:
- Add onicecandidate handlers in createOffers() after getting offer IDs
- Add onicecandidate handler in publishInitialService() after publishing
- Handlers send candidates to server via addIceCandidates()

This fixes the "all checks completed success=0 fail=1" error where
remote candidates were empty.

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

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

src/service-pool.ts

@@ -417,6 +417,25 @@ export class ServicePool {
       const createdOffers = await this.offersApi.create(offerRequests);
       offers.push(...createdOffers);
 
+      // Set up ICE candidate handlers AFTER we have offer IDs
+      for (let i = 0; i < peerConnections.length; i++) {
+        const pc = peerConnections[i];
+        const offerId = createdOffers[i].id;
+
+        pc.onicecandidate = async (event) => {
+          if (event.candidate) {
+            const candidateData = event.candidate.toJSON();
+            if (candidateData.candidate && candidateData.candidate !== '') {
+              try {
+                await this.offersApi.addIceCandidates(offerId, [candidateData]);
+              } catch (err) {
+                console.error('Error sending ICE candidate:', err);
+              }
+            }
+          }
+        };
+      }
+
     } catch (error) {
       // Close any created peer connections on error
       peerConnections.forEach(pc => pc.close());
@@ -493,6 +512,20 @@ export class ServicePool {
 
     const data = await response.json();
 
+    // Set up ICE candidate handler now that we have the offer ID
+    pc.onicecandidate = async (event) => {
+      if (event.candidate) {
+        const candidateData = event.candidate.toJSON();
+        if (candidateData.candidate && candidateData.candidate !== '') {
+          try {
+            await this.offersApi.addIceCandidates(data.offerId, [candidateData]);
+          } catch (err) {
+            console.error('Error sending ICE candidate:', err);
+          }
+        }
+      }
+    };
+
     return {
       serviceId: data.serviceId,
       uuid: data.uuid,