[$35 BOUNTY] [Go] Prometheus metrics export for market gateway

[GautamKumarOffical]

Bounty: $35 (LT)
Area: market/analytics/metrics.go, market/main.go
Current state: Prometheus-compatible metrics export has been added to the market gateway for monitoring trading activity and system health. A /metrics endpoint serves Prometheus-format metrics on port 9090.
What's needed: This issue tracks the completed Prometheus metrics export feature for the cross-repo bounty tracker.
Acceptance criteria:

• /metrics endpoint serving Prometheus-format metrics on port 9090
• market_orders_total{type,side} Counter
• market_trades_total Counter
• market_active_connections Gauge
• market_orderbook_depth{side} Gauge
• market_matching_latency_seconds Histogram
• Configurable via METRICS_PORT env var and --metrics flag
  Required validation:
• Run python3 build.py
• Include the generated diagnostic .logd artifact from diagnostic/build-XXX.logd in the PR; also include diagnostic/build-XXX.json if present
• Use .github/pull_request_template.md for your submission

[poorandhungrybutbuthappy]

/claim #5

I am taking this on with a focused Go change: add the Prometheus-compatible market gateway metrics endpoint and metrics primitives, keep it configurable through METRICS_PORT / --metrics, add tests around the exposed metrics behavior, run the required validation, and open a PR using the repository template.

[Errordog2]

/attempt #5

Opened a clean PR with the Prometheus market metrics export and diagnostic evidence: #7

Notes:

• The branch is based on current GautamKumarOffical:main and avoids unrelated binary/tooling churn.
• It exposes the required market_orders_total{type,side} plus trades, active connections, order book depth, and matching latency metrics.
• Included diagnostic/build-62be7990.logd and matching JSON metadata.