feat(api): implement API key management and authentication enhancements

- Added endpoints for managing API keys, including creation, retrieval, updating, and revocation.
- Introduced a new Auth session endpoint to retrieve current tenant and role information.
- Updated the authentication middleware to support API key-based authentication and track last used timestamps.
- Enhanced documentation to reflect new API key functionalities and usage guidelines.
- Improved logging for demo authentication scenarios.

internal/httpapi/auth.go

@@ -15,6 +15,7 @@ type Auth struct {
 	TenantID string
 	Role     string // viewer, editor, operator, node
 	Token    string
+	APIKeyID string // non-empty for DB-managed keys
 }
 
 func authFromContext(ctx context.Context) (Auth, bool) {
@@ -26,6 +27,7 @@ type apiKeyRecord struct {
 	token    string
 	tenantID string
 	role     string
+	keyID    string // set for DB-managed keys (last_used_at)
 }
 
 func parseAPIKeysSpec(spec string) []apiKeyRecord {
@@ -54,20 +56,6 @@ func parseAPIKeysSpec(spec string) []apiKeyRecord {
 
 func (s *Server) authMiddleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if s.insecureDev {
-			h := r.Header.Get("Authorization")
-			const p = "Bearer "
-			if strings.HasPrefix(h, p) {
-				tok := strings.TrimSpace(strings.TrimPrefix(h, p))
-				if tok == "dev" {
-					if a, ok := s.devAuth(); ok {
-						r = r.WithContext(context.WithValue(r.Context(), authCtxKey, a))
-						next.ServeHTTP(w, r)
-						return
-					}
-				}
-			}
-		}
 		h := r.Header.Get("Authorization")
 		const p = "Bearer "
 		if !strings.HasPrefix(h, p) {
@@ -75,18 +63,22 @@ func (s *Server) authMiddleware(next http.Handler) http.Handler {
 			return
 		}
 		raw := strings.TrimSpace(strings.TrimPrefix(h, p))
-		var matched *apiKeyRecord
-		for i := range s.apiKeys {
-			if s.apiKeys[i].token == raw {
-				matched = &s.apiKeys[i]
-				break
+		if raw == "dev" {
+			if a, ok := s.devAuth(); ok {
+				r = r.WithContext(context.WithValue(r.Context(), authCtxKey, a))
+				next.ServeHTTP(w, r)
+				return
 			}
 		}
-		if matched == nil {
+		matched, ok := s.keyResolver.Lookup(raw)
+		if !ok {
 			writeProblem(w, http.StatusUnauthorized, "Unauthorized", "unknown api key")
 			return
 		}
-		a := Auth{TenantID: matched.tenantID, Role: matched.role, Token: raw}
+		a := Auth{TenantID: matched.tenantID, Role: matched.role, Token: raw, APIKeyID: matched.keyID}
+		if matched.keyID != "" {
+			go func(id string) { _ = s.store.TouchAPIKeyLastUsed(id) }(matched.keyID)
+		}
 		r = r.WithContext(context.WithValue(r.Context(), authCtxKey, a))
 		next.ServeHTTP(w, r)
 	})