Create config model for client-proxy

[djeebus]

Pre-requisite for supporting multiple orchestrators running on a single node.

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Note

Introduce a typed env-based config and refactor logging, service discovery, pools, and main to use it (with ports as uint16) instead of raw env vars.

• Config:
  • Add internal/cfg with Config and ServiceDiscoveryConfig parsed via caarlos0/env (Parse).
  • New env fields for ports, Loki, Redis, SD providers; add SkipInitialOrchestratorReadinessCheck.
• Service Discovery:
  • Replace env-var builder with BuildServiceDiscoveryProvider(cfg, port); create provider constructors accepting cfg.ServiceDiscoveryConfig.
  • Change ServiceDiscoveryItem.NodePort and all SD ports to uint16; update DNS/K8s/Nomad/Static implementations.
  • Add clear error vars for missing config.
• Logging (Loki):
  • GetLogsQueryProvider(cfg) and NewLokiQueryProvider(cfg); use config.LokiURL/User/Password; add ErrEmptyLokiURL.
• Edge API:
  • handlers.NewStore and edge.NewEdgeAPIStore accept cfg.Config; use SkipInitialOrchestratorReadinessCheck.
• Orchestrator/Edge Pools:
  • Port parameters switched to uint16.
• Main:
  • Parse config at startup; remove internal getters and direct env reads.
  • Build SD for Edge/Orchestrator separately; use config for ports, Redis, and flags; update logs to use Uint16 fields.
• Deps/Tests:
  • Add github.com/caarlos0/env/v11 and direct testify dependency.
  • Add internal/cfg/model_test.go for basic parsing.

^{Written by Cursor Bugbot for commit 5a7f2f3. This will update automatically on new commits. Configure here.}

[cursor]

Bug: Unreachable Empty Check for Required URL

The empty check for config.LokiURL in NewLokiQueryProvider is unreachable. Since LokiURL is a required configuration field, cfg.Parse() will prevent application startup if the URL is missing or empty, making the explicit check here redundant.