feat(web): AI 意图规划置信度阈值与动作策略细化

- workbenchAiIntentPlannerModel 新增 WORKBENCH_AI_INTENT_CONFIDENCE_THRESHOLD 与 isLowConfidenceTravelApplicationPlan，shouldRequestWorkbenchAiIntentPlan 增加业务关键词前置过滤
- resolveExecutableTravelApplicationPlan 区分 requestedSubmit 与提交确认（submitRequiresConfirmation），autoSubmit 不再直接置真
- workbenchIntentActionPolicy 改用 policyDecision 路由（need_confirmation/query_candidates），透传 riskLevel/requiresSelection/requiresConfirmation
- workbenchIntentFrameModel 补充 query 动作识别，usePersonalWorkbenchAiMode/useWorkbenchAiActionRouter/useWorkbenchAiApplicationPreviewFlow 接入低置信度与确认流程
- 更新 intent-planner-model/intent-frame-model/application-gate-model/fast-preview 测试

web/src/composables/workbenchAiMode/workbenchAiMessageModel.js

@@ -150,6 +150,8 @@ export function createWorkbenchAiMessageRuntime() {
         ? hydrateInlineAttachmentAssociationSuggestedActions(suggestedActions, normalizedContent)
         : suggestedActions,
       applicationPreview: options.applicationPreview || null,
+      requestedSubmit: Boolean(options.requestedSubmit),
+      submitRequiresConfirmation: Boolean(options.submitRequiresConfirmation),
       draftPayload: options.draftPayload || null,
       attachmentAssociationJob: normalizeInlineAttachmentAssociationJob(options.attachmentAssociationJob || null),
       linkedReimbursementDraftJob: normalizeInlineLinkedReimbursementDraftJob(options.linkedReimbursementDraftJob || null),
@@ -167,6 +169,8 @@ export function createWorkbenchAiMessageRuntime() {
       stewardPlan: message.stewardPlan || null,
       suggestedActions: Array.isArray(message.suggestedActions) ? message.suggestedActions : [],
       applicationPreview: message.applicationPreview || null,
+      requestedSubmit: Boolean(message.requestedSubmit),
+      submitRequiresConfirmation: Boolean(message.submitRequiresConfirmation),
       draftPayload: message.draftPayload || null,
       attachmentAssociationJob: message.attachmentAssociationJob || null,
       linkedReimbursementDraftJob: message.linkedReimbursementDraftJob || null,
@@ -185,6 +189,8 @@ export function createWorkbenchAiMessageRuntime() {
       stewardPlan: message.stewardPlan || null,
       suggestedActions: Array.isArray(message.suggestedActions) ? message.suggestedActions : [],
       applicationPreview: message.applicationPreview || null,
+      requestedSubmit: Boolean(message.requestedSubmit),
+      submitRequiresConfirmation: Boolean(message.submitRequiresConfirmation),
       draftPayload: message.draftPayload || null,
       attachmentAssociationJob: normalizeInlineAttachmentAssociationJob(message.attachmentAssociationJob || null),
       linkedReimbursementDraftJob: normalizeInlineLinkedReimbursementDraftJob(message.linkedReimbursementDraftJob || null),