feat(usage): add Kimi and DeepSeek usage handlers

Wire /v1/usages for Kimi (OAuth + API key) and balance API for DeepSeek,
flag both providers with usage/usageApikey, and normalize their quotas
in the dashboard ProviderLimits parser.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

open-sse/providers/registry/deepseek.js

@@ -48,4 +48,8 @@ export default {
     { id: "deepseek-chat", name: "DeepSeek V3.2 Chat" },
     { id: "deepseek-reasoner", name: "DeepSeek V3.2 Reasoner" },
   ],
+  features: {
+    usage: true,
+    usageApikey: true,
+  },
 };

open-sse/providers/registry/kimi.js

@@ -85,5 +85,8 @@ export default {
   },
   features: {
     usage: true,
+    // API-key connections also hit /v1/usages (x-api-key) — need usageApikey
+    // so isUsageEligible + /api/usage allow non-oauth authType.
+    usageApikey: true,
   },
 };