Initial commit: Luminary AI Gateway

OpenAI-compatible AI gateway with Vue admin UI, multi-provider egress,
ingress key governance, monitoring, and security controls.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/limiter/limiter.go

@@ -0,0 +1,30 @@
+package limiter
+
+import (
+	"github.com/rose_cat707/luminary/internal/model"
+	"github.com/rose_cat707/luminary/internal/store/cache"
+)
+
+func IsProviderKeyAvailable(k model.ProviderKey) bool {
+	if !k.Enabled {
+		return false
+	}
+	if k.MaxRequestsPerDay > 0 && k.RequestsToday >= k.MaxRequestsPerDay {
+		return false
+	}
+	if k.MaxTokensPerDay > 0 && k.TokensToday >= k.MaxTokensPerDay {
+		return false
+	}
+	return true
+}
+
+func CheckIngressBudget(k *model.IngressKey, estimatedCost float64) bool {
+	if k.BudgetLimit <= 0 {
+		return true
+	}
+	return k.BudgetUsed+estimatedCost <= k.BudgetLimit
+}
+
+func CheckRateLimit(c *cache.Store, ingressKeyID uint, rpm, tpm, tokens int) bool {
+	return c.CheckRateLimit(ingressKeyID, rpm, tpm, tokens)
+}