fix(arguments): route "חשב טיעונים" through the legal-analyst agent

The /aggregate-arguments endpoint ran an in-container BackgroundTask that
called claude_session (the local `claude` CLI) — which does not exist in the
FastAPI container. The button silently produced nothing, and on `force` it
destructively DELETEd existing arguments *before* the doomed LLM call.

Replace the inline task with the established delegation pattern used by
"חלץ עובדות שמאיות" (extract-appraiser-facts): a cheap in-container DB
pre-check (no_claims / exists), then a Paperclip wakeup of the company's
legal-analyst, which runs mcp__legal-ai__aggregate_claims_to_arguments
locally (where the CLI lives) and reports back. `force` now runs locally too,
so delete+recompute are atomic on the host — no more destructive failure.

Frontend: AggregateArgumentsResult becomes a discriminated union
(queued | no_claims | exists | skipped) and the toast is status-accurate
instead of the misleading fixed "refresh in a minute".

Invariants: G12 (Paperclip touch confined to paperclip_client behind the
agent_platform_port), G2 (replaces the broken path, no parallel capability),
engineering §6 (explicit statuses, no silent swallow).

UI change is logic/toast only (no visual-layout change) — within the
Claude-Design-gate bug-fix exemption. Richer inline status panels deferred
to the gate.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web-ui/src/components/cases/legal-arguments-panel.tsx

@@ -190,12 +190,27 @@ export function LegalArgumentsPanel({ caseNumber }: LegalArgumentsPanelProps) {
 
   const handleAggregate = (force: boolean) => {
     aggregate.mutate(force, {
-      onSuccess: () => {
-        toast.success(
-          force
-            ? "הופעלה חזרה חישוב טיעונים (force). יסתיים תוך דקה."
-            : "הופעל חישוב טיעונים. רענן בעוד דקה.",
-        );
+      onSuccess: (result) => {
+        switch (result.status) {
+          case "queued":
+            toast.success(
+              force
+                ? "נשלח לאנליטיקאי לחישוב מחדש. התוצאה תופיע תוך כמה דקות — רענן את הדף."
+                : "נשלח לאנליטיקאי. החישוב רץ ברקע; התוצאה תופיע תוך כמה דקות — רענן את הדף.",
+            );
+            break;
+          case "no_claims":
+          case "exists":
+            toast.info(result.message);
+            break;
+          case "skipped":
+            toast.warning(
+              `לא ניתן להפעיל אוטומטית (${result.reason}). הרץ ידנית מ-Claude Code: mcp__legal-ai__aggregate_claims_to_arguments`,
+            );
+            break;
+          default:
+            toast.success("הבקשה נשלחה.");
+        }
       },
       onError: (e) => toast.error(`שגיאה: ${(e as Error).message}`),
     });

web-ui/src/lib/api/legal-arguments.ts

@@ -71,12 +71,30 @@ export function useLegalArguments(caseNumber: string | undefined) {
   });
 }
 
-export type AggregateArgumentsResult = {
-  status: "started" | string;
-  case_number: string;
-  force: boolean;
-  message: string;
-};
+/**
+ * The aggregation runs on the legal-analyst agent (host-side, where the
+ * `claude` CLI lives) — NOT inline in the FastAPI container. The endpoint
+ * either delegates via a Paperclip wakeup (`queued`) or short-circuits on a
+ * cheap in-container DB pre-check (`no_claims` / `exists`). `skipped` means
+ * no analyst route was available; the chair can run the MCP tool manually.
+ */
+export type AggregateArgumentsResult =
+  | {
+      status: "queued";
+      sub_issue_id: string;
+      analyst_id: string;
+      main_issue_id: string;
+    }
+  | {
+      status: "no_claims" | "exists";
+      total: number;
+      message: string;
+    }
+  | {
+      status: "skipped";
+      reason: "no_api_key" | "no_analyst" | "no_issue" | string;
+      company_id?: string;
+    };
 
 export function useAggregateArguments(caseNumber: string | undefined) {
   const qc = useQueryClient();