Refactor AI Agent and AI Config handling across multiple files

- Updated function signatures to accept AI Agent and AI Config as non-pointer types for better clarity and safety.
- Modified instances where AI Agent and AI Config were dereferenced to improve code readability.
- Removed unnecessary nil checks for AI Agent and AI Config, simplifying the logic.
- Adjusted related tests and services to align with the new function signatures.
- Cleaned up code in runtime, skills, and executor packages to ensure consistency in handling AI configurations.

internal/ai/skills/plan_service.go

@@ -3,8 +3,6 @@ package skills
 import (
 	"context"
 	"strings"
-
-	"cs-agent/internal/pkg/errorsx"
 )
 
 func newPlanService() *planService {
@@ -15,13 +13,7 @@ type planService struct{}
 
 // BuildExecutionPlan 构建当前请求的 Skill 执行计划。
 func (s *planService) BuildExecutionPlan(execCtx context.Context, ctx RuntimeContext) (*ExecutionPlan, error) {
-	if ctx.AIAgent == nil {
-		return nil, errorsx.InvalidParam("AIAgent不能为空")
-	}
-	if ctx.AIConfig == nil {
-		return nil, errorsx.InvalidParam("AIConfig不能为空")
-	}
-	skill, matchReason, routeTrace, err := MatchSkill(execCtx, ctx, ctx.AIAgent, ctx.AIConfig)
+	skill, matchReason, routeTrace, err := MatchSkill(execCtx, ctx)
 	if err != nil {
 		return nil, err
 	}