fix(dev): default port :8080 → :8090

Unblock local dev: Keycloak owns :8080, so tenant-registry shifts to :8090. Prod is functionally unchanged.

Refs: M5.1

internal/config/config.go

@@ -7,7 +7,7 @@ import (
 
 type Config struct {
 	Env            string // dev | stage | prod
-	Addr           string // listen address, e.g. ":8080"
+	Addr           string // listen address, e.g. ":8090"
 	KeycloakIssuer string // e.g. http://localhost:8080/realms/breakpilot-dev
 	DatabaseURL    string // postgres DSN (unused in skeleton; in-memory store)
 }
@@ -18,8 +18,9 @@ func Load() (*Config, error) {
 		return nil, fmt.Errorf("invalid APP_ENV %q", env)
 	}
 	return &Config{
-		Env:            env,
-		Addr:           getenv("ADDR", ":8080"),
+		Env: env,
+		// :8090 — Keycloak owns :8080 in the dev stack.
+		Addr:           getenv("ADDR", ":8090"),
 		KeycloakIssuer: getenv("KEYCLOAK_ISSUER", "http://localhost:8080/realms/breakpilot-dev"),
 		DatabaseURL:    os.Getenv("DATABASE_URL"),
 	}, nil