chore: bump egress tracking to 50% (#201)

### Ramp-Up Schedule

> ~1%~ → ~5%~ → ~10%~ → ~25%~ → **50%** → 100%


| Phase | % | Events/s (avg) | Events/s (peak) | Queue % | Start Date |
Duration | |

|-------|---|----------------|-----------------|---------|------------|----------|--|
| **Start** | 1% | 11.5 | 30 | 0.6% | Nov 20 | 1 days | ✅ 
| **Data Collection** | 5% | 57 | 150 | 3% | Nov 22 | 1 days | ✅
| **Analysis** | 10% | 115 | 300 | 6% | Nov 24 | 1 days |✅
| **Ramp** | 25% | 287 | 750 | 15% | Nov 26 | 1 days |✅
| **Major** | 50% | 573 | 1,500 | 30% | Nov 28 | 2 days | 🔧 
| **Full** | 100% | 1,146 | 3,000 | 60% | Nov 30 | Ongoing |

Author: fforbeck

wrangler.toml

@@ -57,7 +57,7 @@ command = "npm run build"
 MAX_SHARDS = "825"
 FF_RATE_LIMITER_ENABLED = "false"
 FF_EGRESS_TRACKER_ENABLED = "true"
-FF_EGRESS_TRACKER_ROLLOUT_PERCENTAGE = "5"  # 5% - 495K events/day, ~60 req/s avg
+FF_EGRESS_TRACKER_ROLLOUT_PERCENTAGE = "50"  # 50% - 5M events/day, ~600 req/s avg (queue limit 5K req/sec)
 FF_TELEMETRY_ENABLED = "false" # FIXME: telemetry is causing directory listings to fail.
 FF_DELEGATIONS_STORAGE_ENABLED = "true"
 FF_RAMP_UP_PROBABILITY = "100"