fix(tools): normalize agent_id before self-check and delegation

Apply routing.NormalizeAgentID to the raw agent_id input before any
logic runs. This prevents case/whitespace variants like "ALPHA" or
" alpha " from bypassing the self-delegation guard while still
resolving to the same agent in the registry.

The normalized value is used consistently for self-check, allowlist,
SpawnSubTurn, and result attribution.

Ref: #2148

pkg/tools/delegate.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"fmt"
 	"strings"
+
+	"github.com/sipeed/picoclaw/pkg/routing"
 )
 
 // DelegateTool delegates a task to a specific named agent and waits for
@@ -61,10 +63,11 @@ func (t *DelegateTool) Parameters() map[string]any {
 }
 
 func (t *DelegateTool) Execute(ctx context.Context, args map[string]any) *ToolResult {
-	agentID, _ := args["agent_id"].(string)
-	if strings.TrimSpace(agentID) == "" {
+	rawAgentID, _ := args["agent_id"].(string)
+	if strings.TrimSpace(rawAgentID) == "" {
 		return ErrorResult("agent_id is required and must be a non-empty string")
 	}
+	agentID := routing.NormalizeAgentID(rawAgentID)
 
 	task, _ := args["task"].(string)
 	if strings.TrimSpace(task) == "" {