feat(dashboard): scoped API keys with rate limits and quotas

Bearer keys (dlk_...) are checked per request against their owner's
current account (ban, lock, demotion, sign out everywhere stop or narrow
them at once) and their scope: permission routes need the permission in
scope, read-only keys only read, level-only routes need an all-permission
key, and session-only paths (sign-in, password, 2FA, key management)
are never reachable with a key. Per-key rate limit and daily quota with
429 and X-RateLimit/X-Quota/Retry-After headers; usage is written in
batches every minute. WebSocket subscriptions honour the scope too.

Routes to list, make, rotate and revoke keys; staff with
api_keys_manage can see and revoke others' keys under the rank rules.
POST /api/auth/token now makes an all-permission key. Audit entries for
create/rotate/revoke/denied, and actions done with a key are attributed
to "user (key name)".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dWeb/HTTPContext.h

@@ -6,6 +6,7 @@
 #include <algorithm>
 #include "eHTTPStatusCode.h"
 #include "json.hpp"
+#include "ApiKeyScope.h"
 
 /**
  * HTTP Request Context
@@ -34,6 +35,9 @@ struct HTTPContext {
 	std::string authenticatedUser{};
 	uint32_t accountId = 0;
 	uint8_t gmLevel = 0;
+	// Set when an API key authenticated the request: the key's scope, on top of what the account may do (gmLevel).
+	// Every permission check must honour it (RouteUtils::Can and friends do).
+	std::shared_ptr<const ApiKeys::Scope> apiKey{};
 	
 	// Custom data for middleware to communicate
 	std::map<std::string, std::string> userData{};