feat(hooks): add BeforeOp hook and fix BeforeScan row-security gap

Adds a BeforeOp HookType across resolvespec, restheadspec, websocketspec,
mqttspec, and funcspec that fires before every SQL operation (read,
create, update, delete, scan/query) via a new ExecuteBeforeOp helper.

Also closes a row-level-security gap: resolvespec registered a BeforeScan
hook for ApplyRowSecurity but never fired it, and websocketspec/mqttspec
had no BeforeScan hook point at all, so row security was never applied
to their queries. BeforeScan now fires right before the actual scan in
all three, with the (possibly hook-modified) query used for execution.

pkg/mqttspec/handler.go

@@ -313,7 +313,7 @@ func (h *Handler) handleRequest(client *Client, msg *Message) {
 // handleRead processes a read operation
 func (h *Handler) handleRead(client *Client, msg *Message, hookCtx *HookContext) {
 	// Execute before hook
-	if err := h.hooks.Execute(BeforeRead, hookCtx); err != nil {
+	if err := h.hooks.ExecuteBeforeOp(BeforeRead, hookCtx); err != nil {
 		logger.Error("[MQTTSpec] BeforeRead hook failed: %v", err)
 		h.sendError(client.ID, msg.ID, "hook_error", err.Error())
 		return
@@ -356,7 +356,7 @@ func (h *Handler) handleRead(client *Client, msg *Message, hookCtx *HookContext)
 // handleCreate processes a create operation
 func (h *Handler) handleCreate(client *Client, msg *Message, hookCtx *HookContext) {
 	// Execute before hook
-	if err := h.hooks.Execute(BeforeCreate, hookCtx); err != nil {
+	if err := h.hooks.ExecuteBeforeOp(BeforeCreate, hookCtx); err != nil {
 		logger.Error("[MQTTSpec] BeforeCreate hook failed: %v", err)
 		h.sendError(client.ID, msg.ID, "hook_error", err.Error())
 		return
@@ -390,7 +390,7 @@ func (h *Handler) handleCreate(client *Client, msg *Message, hookCtx *HookContex
 // handleUpdate processes an update operation
 func (h *Handler) handleUpdate(client *Client, msg *Message, hookCtx *HookContext) {
 	// Execute before hook
-	if err := h.hooks.Execute(BeforeUpdate, hookCtx); err != nil {
+	if err := h.hooks.ExecuteBeforeOp(BeforeUpdate, hookCtx); err != nil {
 		logger.Error("[MQTTSpec] BeforeUpdate hook failed: %v", err)
 		h.sendError(client.ID, msg.ID, "hook_error", err.Error())
 		return
@@ -424,7 +424,7 @@ func (h *Handler) handleUpdate(client *Client, msg *Message, hookCtx *HookContex
 // handleDelete processes a delete operation
 func (h *Handler) handleDelete(client *Client, msg *Message, hookCtx *HookContext) {
 	// Execute before hook
-	if err := h.hooks.Execute(BeforeDelete, hookCtx); err != nil {
+	if err := h.hooks.ExecuteBeforeOp(BeforeDelete, hookCtx); err != nil {
 		logger.Error("[MQTTSpec] BeforeDelete hook failed: %v", err)
 		h.sendError(client.ID, msg.ID, "hook_error", err.Error())
 		return
@@ -686,6 +686,18 @@ func (h *Handler) readByID(hookCtx *HookContext) (interface{}, error) {
 		}
 	}
 
+	// Execute BeforeScan hooks - pass query so hooks (e.g. row-level security) can modify it
+	if hookCtx.Metadata == nil {
+		hookCtx.Metadata = make(map[string]interface{})
+	}
+	hookCtx.Metadata["query"] = query
+	if err := h.hooks.ExecuteBeforeOp(BeforeScan, hookCtx); err != nil {
+		return nil, fmt.Errorf("BeforeScan hook failed: %w", err)
+	}
+	if modifiedQuery, ok := hookCtx.Metadata["query"].(common.SelectQuery); ok {
+		query = modifiedQuery
+	}
+
 	// Execute query
 	if err := query.ScanModel(hookCtx.Context); err != nil {
 		return nil, fmt.Errorf("failed to read record: %w", err)
@@ -738,6 +750,18 @@ func (h *Handler) readMultiple(hookCtx *HookContext) (data interface{}, metadata
 		}
 	}
 
+	// Execute BeforeScan hooks - pass query so hooks (e.g. row-level security) can modify it
+	if hookCtx.Metadata == nil {
+		hookCtx.Metadata = make(map[string]interface{})
+	}
+	hookCtx.Metadata["query"] = query
+	if err := h.hooks.ExecuteBeforeOp(BeforeScan, hookCtx); err != nil {
+		return nil, nil, fmt.Errorf("BeforeScan hook failed: %w", err)
+	}
+	if modifiedQuery, ok := hookCtx.Metadata["query"].(common.SelectQuery); ok {
+		query = modifiedQuery
+	}
+
 	// Execute query
 	if err := query.ScanModel(hookCtx.Context); err != nil {
 		return nil, nil, fmt.Errorf("failed to read records: %w", err)