compaction de contexte, filtre/pagination/suppression des conversations

- compaction automatique du contexte LLM quand la taille atteint le seuil
  (contexte max - taille de réponse max), par résumé de l'historique ancien
- filtre textuel (?q=) et pagination (20/page) de l'historique des conversations
- correctif ORM : offset de pagination en base 0
- suppression d'une conversation : messages associés supprimés, session en
  cours annulée, popup de confirmation (ConfirmDialog)
- titres de conversation nettoyés du markdown
- styles des listes markdown, variante danger du bouton
- go.mod/go.sum : dépendances go-rod et stealth manquantes du commit précédent

backend/web/src/lib/api/endpoints/chat.ts

@@ -4,7 +4,8 @@ import type { Chat, Chunk, ChatRequest, ChatWithMessages } from "$lib/types/api"
 export const chatApi = {
   createChat: (space: string, data: Partial<ChatRequest>) => api.post<Chat>(`/chat/${space}`, data),
   createChatMessage: (space: string, id: string, data: Partial<ChatRequest>) => api.postStream<Chunk>(`/chat/${space}/${id}`, data),
-  allChats: (space: string, pageNum: number) => api.get<Chat[]>(`/chat/${space}/all/${pageNum}`),
+  allChats: (space: string, pageNum: number, query?: string) =>
+    api.get<Chat[]>(`/chat/${space}/all/${pageNum}${query ? `?q=${encodeURIComponent(query)}` : ''}`),
   getChat: (space: string, id: string) => api.get<ChatWithMessages>(`/chat/${space}/${id}`),
   subscribe: (space: string, id: string) => api.get<ChatWithMessages>(`/chat/${space}/${id}/subscribe`),
   deleteChat: (space: string, id: string) => api.delete(`/chat/${space}/${id}`),

backend/web/src/lib/components/ConfirmDialog.svelte

@@ -0,0 +1,60 @@
+<script lang="ts">
+  import { fade, scale } from "svelte/transition";
+
+  let {
+    open = false,
+    title = "",
+    message = "",
+    confirmLabel = "Confirmer",
+    cancelLabel = "Annuler",
+    onConfirm,
+    onCancel,
+  }: {
+    open?: boolean;
+    title?: string;
+    message?: string;
+    confirmLabel?: string;
+    cancelLabel?: string;
+    onConfirm?: () => void;
+    onCancel?: () => void;
+  } = $props();
+
+  const close = () => onCancel?.();
+
+  const handleKeydown = (e: KeyboardEvent) => {
+    if (open && e.key === "Escape") close();
+  };
+</script>
+
+<svelte:window onkeydown={handleKeydown} />
+
+{#if open}
+  <div class="fixed inset-0 z-50 flex items-center justify-center p-4">
+    <button
+      type="button"
+      class="absolute inset-0 cursor-default bg-black/50"
+      aria-label="Fermer"
+      onclick={close}
+      transition:fade={{ duration: 150 }}
+    ></button>
+    <div
+      class="relative w-full max-w-sm rounded-lg bg-stone-50 p-4 shadow-xl dark:bg-stone-900"
+      role="dialog"
+      aria-modal="true"
+      aria-labelledby="confirm-dialog-title"
+      transition:scale={{ duration: 150, start: 0.95 }}
+    >
+      <div class="flex items-center gap-3">
+        <div class="flex h-9 w-9 shrink-0 items-center justify-center rounded-full bg-red-100 text-red-600 dark:bg-red-950 dark:text-red-400">
+            <i class="icon-trash-empty"></i>
+        </div>
+        <h2 id="confirm-dialog-title" class="text-base font-bold">{title}</h2>
+      </div>
+      <p class="mt-3 text-sm text-stone-600 dark:text-stone-400">{message}</p>
+      <div class="mt-4 flex justify-end gap-2">
+        <button type="button" class="bt small" onclick={close}>{cancelLabel}</button>
+        <button type="button" class="bt small danger" onclick={onConfirm}>{confirmLabel}</button>
+      </div>
+    </div>
+  </div>
+{/if}

backend/web/src/routes/(authenticated)/[space]/history/+page.svelte

@@ -1,15 +1,114 @@
 <script lang="ts">
+    import { invalidateAll } from "$app/navigation";
+    import { chatApi } from "$lib/api/endpoints/chat";
+    import { putMessage } from "$lib/state/toaster.svelte";
+    import ConfirmDialog from "$lib/components/ConfirmDialog.svelte";
     import type { PageProps } from './$types';
+    import type { Chat } from "$lib/types/api";
     let { data }: PageProps = $props();
+
+    const PAGE_SIZE = 20;
+
+    let search = $state("");
+    // svelte-ignore state_referenced_locally -- la liste est gérée localement
+    // (filtre, pagination, suppression) et ne doit pas suivre les rechargements de data
+    let conversations = $state<Chat[]>(data.conversations);
+    let page = $state(0);
+    let loading = $state(false);
+    let conversationToDelete = $state<Chat | null>(null);
+
+    const hasMore = $derived(conversations.length === (page + 1) * PAGE_SIZE);
+
+    let searchTimer: ReturnType<typeof setTimeout> | undefined;
+
+    const handleSearch = () => {
+        if (searchTimer !== undefined) clearTimeout(searchTimer);
+        searchTimer = setTimeout(async () => {
+            page = 0;
+            const result = await chatApi.allChats(data.space, 0, search);
+            conversations = result ?? [];
+        }, 300);
+    };
+
+    const loadMore = async () => {
+        if (loading) return;
+        loading = true;
+        try {
+            const result = await chatApi.allChats(data.space, page + 1, search);
+            const next = result ?? [];
+            conversations = [...conversations, ...next];
+            page += 1;
+        } catch {
+            putMessage("failure", "Erreur lors du chargement des conversations");
+        } finally {
+            loading = false;
+        }
+    };
+
+    const handleDelete = async () => {
+        if (!conversationToDelete) return;
+        try {
+            await chatApi.deleteChat(data.space, conversationToDelete.id);
+            putMessage("success", "Conversation supprimée");
+            await invalidateAll();
+            const result = await chatApi.allChats(data.space, 0, search);
+            conversations = result ?? [];
+            page = 0;
+        } catch {
+            putMessage("failure", "Erreur lors de la suppression de la conversation");
+        } finally {
+            conversationToDelete = null;
+        }
+    };
 </script>
 
 <div class="container">
-    {#each data.conversations as conversation (conversation.id)}
+    <div class="formelement my-2">
+        <input
+            class="textinput"
+            type="search"
+            placeholder="Rechercher une conversation..."
+            bind:value={search}
+            oninput={handleSearch}
+        />
+    </div>
+
+    {#each conversations as conversation (conversation.id)}
         <div class="dark:bg-stone-800 rounded p-2 my-2">
-            <div class="font-bold text-base">
-                <a href={`/${data.space}/${conversation.id}`}>{conversation.title}</a>
+            <div class="flex flex-row items-center">
+                <div class="flex-1 font-bold text-base">
+                    <a href={`/${data.space}/${conversation.id}`}>{conversation.title}</a>
+                </div>
+                <button
+                    class="bt small"
+                    title="Supprimer la conversation"
+                    onclick={() => (conversationToDelete = conversation)}
+                >
+                    <i class="icon-trash-empty"></i>
+                </button>
             </div>
             <span class="text-xs">{conversation._date_created}</span>
         </div>
     {/each}
+
+    {#if conversations.length === 0}
+        <p class="my-4 text-center text-sm text-stone-500">Aucune conversation trouvée.</p>
+    {/if}
+
+    {#if hasMore}
+        <div class="my-4 text-center">
+            <button class="bt small" disabled={loading} onclick={loadMore}>
+                {loading ? "Chargement..." : "Charger plus"}
+            </button>
+        </div>
+    {/if}
 </div>
+
+<ConfirmDialog
+    open={conversationToDelete !== null}
+    title="Supprimer la conversation"
+    message={`Voulez-vous vraiment supprimer « ${conversationToDelete?.title} » ? Cette action est irréversible.`}
+    confirmLabel="Supprimer"
+    onConfirm={handleDelete}
+    onCancel={() => (conversationToDelete = null)}
+/>

backend/web/src/routes/layout.css

@@ -44,6 +44,9 @@ h2 {
 	&.error {
 		@apply bg-red-300 dark:bg-red-700;
 	}
+	&.danger {
+		@apply bg-red-500 text-white hover:bg-red-600 dark:bg-red-700 dark:hover:bg-red-600;
+	}
 	&.disabled {
 		@apply text-stone-400 hover:bg-stone-200 dark:hover:bg-stone-800;
 	}
@@ -292,7 +295,15 @@ h2 {
 
 	ul,
 	ol {
-		@apply my-2;
+		@apply my-2 pl-5;
+	}
+
+	ul li {
+		@apply list-disc pl-2;
+	}
+
+	ol li {
+		@apply list-decimal pl-2;
 	}
 
 	h1 {
@@ -315,10 +326,6 @@ h2 {
 		@apply text-sm;
 	}
 
-	li {
-		@apply ml-5 list-disc pl-4 marker:text-xl;
-	}
-
 	pre {
 		@apply my-2 rounded px-2 py-1 text-xs dark:bg-stone-700;
 	}