fix: livrable tickets #70 #100 #102 — UX surface scoping

- #70: implémentation suppression modèles locaux téléchargés
- #100: correction scroll OpenCode
- #102: correction fit TUI après switch/layout
- memory note scoping UX

frontend/src/features/model-servers/ModelServersPanel.tsx

@@ -15,6 +15,7 @@ import { useEffect, useRef, useState } from "react";
 
 import type {
   LocalModelServerConfig,
+  ModelArtifact,
   ModelServerCommandPreview,
   ModelSource,
   StopPolicy,
@@ -47,6 +48,35 @@ const STOP_POLICIES: { value: StopPolicy; label: string }[] = [
   { value: "stopWhenUnused", label: "Stop when unused" },
 ];
 
+function formatBytes(bytes: number): string {
+  if (!Number.isFinite(bytes) || bytes < 0) return "";
+  const units = ["B", "KB", "MB", "GB", "TB"] as const;
+  let value = bytes;
+  let unit = 0;
+  while (value >= 1000 && unit < units.length - 1) {
+    value /= 1000;
+    unit += 1;
+  }
+  const digits = unit === 0 || value >= 10 ? 0 : 1;
+  return `${value.toFixed(digits)} ${units[unit]}`;
+}
+
+function deleteArtifactConfirmation(
+  server: LocalModelServerConfig,
+  artifact: Extract<ModelArtifact, { state: "downloaded" }>,
+): string {
+  const size =
+    artifact.sizeBytes == null ? "" : `Espace libéré : ${formatBytes(artifact.sizeBytes)}.`;
+  return [
+    "Supprimer le modèle téléchargé ?",
+    `Serveur : ${server.name}`,
+    "Le serveur local restera configuré, mais IdeA devra retélécharger ce modèle au prochain lancement.",
+    size,
+  ]
+    .filter(Boolean)
+    .join("\n");
+}
+
 export interface ModelServersPanelProps {
   /** The model-server registry view-model (from `useModelServers`). */
   vm: ModelServersViewModel;
@@ -73,6 +103,14 @@ export function ModelServersPanel({ vm }: ModelServersPanelProps) {
     if (saved) setDraft(null);
   }
 
+  async function confirmDeleteArtifact(
+    server: LocalModelServerConfig,
+    artifact: Extract<ModelArtifact, { state: "downloaded" }>,
+  ) {
+    if (!window.confirm(deleteArtifactConfirmation(server, artifact))) return;
+    await vm.deleteArtifact(server.id);
+  }
+
   return (
     <Panel
       aria-label="local model servers"
@@ -98,6 +136,11 @@ export function ModelServersPanel({ vm }: ModelServersPanelProps) {
             {vm.error}
           </p>
         )}
+        {vm.notice && (
+          <p role="status" className="text-sm text-muted">
+            {vm.notice}
+          </p>
+        )}
 
         {vm.servers.length === 0 && !draft && (
           <p className="text-xs text-muted">
@@ -107,40 +150,69 @@ export function ModelServersPanel({ vm }: ModelServersPanelProps) {
         )}
 
         <ul className="flex list-none flex-col gap-2 p-0">
-          {vm.servers.map((server) => (
-            <li
-              key={server.id}
-              className="flex items-center gap-2 rounded-md border border-border bg-raised p-2"
-            >
-              <span className="flex min-w-0 flex-col">
-                <strong className="truncate text-sm text-content">
-                  {server.name}
-                </strong>
-                <span className="truncate text-xs text-muted">
-                  {server.baseURL} · {server.servedModelName}
-                  {server.autoStart ? " · auto-start" : ""}
+          {vm.servers.map((server) => {
+            const artifact = server.artifact;
+            const downloaded =
+              artifact?.state === "downloaded" ? artifact : undefined;
+            const deletingArtifact = vm.deletingArtifactId === server.id;
+            const downloadingArtifact = artifact?.state === "downloading";
+            return (
+              <li
+                key={server.id}
+                className="flex items-center gap-2 rounded-md border border-border bg-raised p-2"
+              >
+                <span className="flex min-w-0 flex-col">
+                  <strong className="truncate text-sm text-content">
+                    {server.name}
+                  </strong>
+                  <span className="truncate text-xs text-muted">
+                    {server.baseURL} · {server.servedModelName}
+                    {server.autoStart ? " · auto-start" : ""}
+                  </span>
                 </span>
-              </span>
-              <span className="ml-auto flex items-center gap-1">
-                <Button
-                  size="sm"
-                  aria-label={`edit ${server.name}`}
-                  onClick={() => startEdit(server)}
-                  disabled={vm.busy}
-                >
-                  Edit
-                </Button>
-                <IconButton
-                  size="sm"
-                  aria-label={`delete ${server.name}`}
-                  onClick={() => void vm.remove(server.id)}
-                  disabled={vm.busy}
-                >
-                  ×
-                </IconButton>
-              </span>
-            </li>
-          ))}
+                <span className="ml-auto flex items-center gap-1">
+                  {downloadingArtifact && (
+                    <Button
+                      size="sm"
+                      variant="secondary"
+                      aria-label={`download in progress ${server.name}`}
+                      disabled
+                    >
+                      Téléchargement en cours
+                    </Button>
+                  )}
+                  {downloaded && (
+                    <Button
+                      size="sm"
+                      variant="danger"
+                      aria-label={`delete downloaded model ${server.name}`}
+                      onClick={() => void confirmDeleteArtifact(server, downloaded)}
+                      loading={deletingArtifact}
+                      disabled={vm.busy && !deletingArtifact}
+                    >
+                      {deletingArtifact ? "Suppression..." : "Supprimer le modèle téléchargé"}
+                    </Button>
+                  )}
+                  <Button
+                    size="sm"
+                    aria-label={`edit ${server.name}`}
+                    onClick={() => startEdit(server)}
+                    disabled={vm.busy}
+                  >
+                    Edit
+                  </Button>
+                  <IconButton
+                    size="sm"
+                    aria-label={`delete ${server.name}`}
+                    onClick={() => void vm.remove(server.id)}
+                    disabled={vm.busy}
+                  >
+                    ×
+                  </IconButton>
+                </span>
+              </li>
+            );
+          })}
         </ul>
 
         {draft && (