feat(edge): wire HTTP API to message bus

[barton87]

Summary

Closes #22.

Implements the Edge HTTP Server bounty with a focused, test-backed API surface:

• Adds required endpoints:
  • GET /api/health
  • GET /api/status
  • POST /api/command
  • POST /api/message
• Preserves compatibility aliases:
  • GET /healthz
  • GET /api/v1/health
  • GET /api/v1/status
  • POST /api/v1/command
  • POST /api/v1/message
• Wires the gateway MessageBus into the edge server so accepted commands/messages are published instead of only logged.
• Adds structured JSON responses/errors and useful status fields (bus_connected, endpoint list, node/cloud info).
• Adds focused pkg/edge tests for route aliases, command/message publishing, invalid requests, and no-bus behavior.
• Fixes a deterministic ordering issue in pkg/gene.SelectGenes so the repository-wide test suite passes; this is separate from the edge API behavior but required for clean validation.

Validation

• gofmt -w cmd/picoclaw/main.go pkg/edge/server.go pkg/edge/server_test.go pkg/gene/selector.go
• go test ./pkg/edge ./pkg/bus ./cmd/picoclaw
• go test ./...

Notes

The implementation keeps the edge API small and avoids changing unrelated agent-loop behavior. Command/message requests are accepted into the existing bus with metadata so downstream handlers can process them consistently.