Add timing instrumentation to MCP gateway setup scripts

[Copilot]

Adds millisecond-precision timing to identify startup performance bottlenecks in MCP gateway initialization.

Changes

Modified scripts:

• check_mcp_servers.sh - Times config validation, per-server checks, overall execution
• start_mcp_gateway.sh - Times config I/O, validation, container launch, health polling, conversion, server checks, total startup
• verify_mcp_gateway_health.sh - Times health polling, config verification, connectivity tests, total verification

Implementation:

print_timing() {
  local start_time=$1
  local label=$2
  local end_time=$(date +%s%3N)
  local duration=$((end_time - start_time))
  echo "⏱️  TIMING: $label took ${duration}ms"
}

Example output:

⏱️  TIMING: Configuration validation took 156ms
⏱️  TIMING: Server check for github took 2347ms
⏱️  TIMING: Health check wait took 42156ms
⏱️  TIMING: Overall gateway startup took 48159ms

All timing prefixed with ⏱️ TIMING: for log filtering: grep "⏱️ TIMING:" logs

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.