fix(deploy): resolve Railway deployment configuration issues

- Remove conflicting railway.json (was overriding railway.toml)
- Update railway.toml healthcheck timeout from 100s to 300s
- Rename service from 'lexecon-backend' to 'lexecon'
- Reduce maxRetries from 10 to 3 for faster failure detection

The conflicting railway.json had a different start command that didn't
run migrations, causing database schema issues on fresh deployments.

Author: Lexecon Dev

railway.json

@@ -5,9 +5,9 @@ dockerfilePath = "Dockerfile"
 [deploy]
 startCommand = "/bin/sh /app/start.sh"
 healthcheckPath = "/health"
-healthcheckTimeout = 100
+healthcheckTimeout = 300
 restartPolicyType = "ON_FAILURE"
-restartPolicyMaxRetries = 10
+restartPolicyMaxRetries = 3
 
 [[services]]
-name = "lexecon-backend"
+name = "lexecon"