feat(ai): assistant AI multi-contexte + ergonomie sidebar et clavier

Contexte:
- Repertoire (mode historique BooksLM, via menu contextuel dossier)
- Documents (bouton flottant quand des documents sont ouverts)
- General (bouton flottant sans document: aide app + creation de fichiers)
- Le contexte est affiche dans le header; suggestions adaptees au mode
- Blocs obsigate-action rendus en carte avec bouton Appliquer (pas d'execution auto)

Backend:
- /api/ai/bookslm/context et /chat acceptent mode + context_files
- collect_files_context(), empty_context(), build_general_system_prompt()
- mode documents degrade vers general si aucun fichier lisible

Corrige:
- bouton flottant passait le chemin d'un fichier comme repertoire -> erreur
  'Aucun fichier markdown trouve dans ce dossier'
- panneau precedent masque (localStorage) ne se rouvrait plus
- selecteur fournisseur/modele deplace sur une ligne dediee (header actions visibles)
- Entree envoie, Ctrl+Entree insere un saut de ligne

Tests: test_bookslm.py (+13) et tests/frontend/ai.test.mjs (+8)

tests/frontend/ai.test.mjs

@@ -103,6 +103,7 @@ async function main() {
   const ai = await import(pathToFileURL(path.join(JS_DIR, "ai.js")).href);
   const bookslmMod = await import(pathToFileURL(path.join(JS_DIR, "bookslm.js")).href);
   const { BooksLM } = bookslmMod;
+  const { collectOpenDocuments, documentsSignature } = bookslmMod;
 
   // ── 1. Rewrite modal resolves with the typed instruction ──
   await test("rewrite modal returns the typed instruction on confirm", async () => {
@@ -226,12 +227,146 @@ async function main() {
     assert.deepEqual(missingEn, [], `missing EN keys: ${missingEn.join(", ")}`);
   });
 
+  // ── 7. Context detection: open documents across tabs and panes ──
+  await test("collectOpenDocuments merges tabs and panes without duplicates", () => {
+    window.TabManager = {
+      _activeTabId: "t1",
+      _tabs: [
+        { id: "t1", vault: "V", path: "a.md" },
+        { id: "t2", vault: "V", path: "b.md" },
+      ],
+    };
+    window.PaneManager = {
+      tabManagers: {
+        0: {
+          _activeTabId: "p1",
+          _tabs: [
+            { id: "p1", vault: "V", path: "b.md" },
+            { id: "p2", vault: "W", path: "c.md" },
+          ],
+        },
+      },
+    };
+    const docs = collectOpenDocuments();
+    assert.equal(docs.length, 3, "b.md must be de-duplicated");
+    assert.equal(docs[0].path, "a.md", "active tab first");
+    delete window.TabManager;
+    delete window.PaneManager;
+  });
+
+  await test("documentsSignature is stable", () => {
+    const sig = documentsSignature([{ vault: "V", path: "a.md" }, { vault: "V", path: "b.md" }]);
+    assert.equal(sig, "V/a.md\u0000V/b.md");
+    assert.equal(documentsSignature([]), "");
+  });
+
+  await test("openForCurrentContext picks documents when tabs are open", async () => {
+    window.TabManager = {
+      _activeTabId: "t1",
+      _tabs: [
+        { id: "t1", vault: "V", path: "notes/a.md" },
+        { id: "t2", vault: "V", path: "notes/b.md" },
+      ],
+    };
+    let ctxBody = null;
+    globalThis.fetch = async (url, opts) => {
+      const u = String(url);
+      if (u.includes("/api/ai/status")) {
+        return { ok: true, status: 200, json: async () => ({ configured: true, providers: {} }) };
+      }
+      if (u.includes("/api/ai/bookslm/context")) {
+        ctxBody = JSON.parse(opts.body);
+        return {
+          ok: true,
+          status: 200,
+          json: async () => ({ files: [{ path: "notes/a.md" }], total_chars: 10, file_count: 1, scope: "documents", max_total_chars: 200000 }),
+        };
+      }
+      return { ok: true, status: 200, json: async () => ({}) };
+    };
+    const b = new BooksLM();
+    await b.openForCurrentContext();
+    assert.equal(b._mode, "documents");
+    assert.equal(ctxBody.mode, "documents");
+    assert.deepEqual(ctxBody.context_files, ["notes/a.md", "notes/b.md"]);
+    await sleep(10);
+    assert.ok(b._panel.classList.contains("open"));
+    b.close();
+    delete window.TabManager;
+  });
+
+  await test("openForCurrentContext falls back to general with no document", async () => {
+    window.TabManager = { _activeTabId: null, _tabs: [] };
+    const b = new BooksLM();
+    await b.openForCurrentContext();
+    assert.equal(b._mode, "general");
+    await sleep(10);
+    assert.ok(b._panel.classList.contains("open"));
+    assert.ok(!b._panel.classList.contains("hidden"), "explicit open must reveal the panel");
+    b.close();
+    delete window.TabManager;
+  });
+
+  // ── 8. Keyboard behaviour: Enter sends, Ctrl+Enter adds a line ──
+  await test("Enter submits and Ctrl+Enter inserts a newline", () => {
+    const b = new BooksLM();
+    b._panel = b._render();
+    document.body.appendChild(b._panel);
+    b._isOpen = true;
+    let sent = 0;
+    b._sendMessage = () => { sent++; };
+
+    const textarea = b._panel.querySelector("textarea");
+    textarea.value = "hello";
+    textarea.dispatchEvent(new window.KeyboardEvent("keydown", { key: "Enter", bubbles: true, cancelable: true }));
+    assert.equal(sent, 1, "Enter should submit");
+
+    textarea.value = "line1";
+    textarea.selectionStart = textarea.selectionEnd = 5;
+    textarea.dispatchEvent(new window.KeyboardEvent("keydown", { key: "Enter", ctrlKey: true, bubbles: true, cancelable: true }));
+    assert.equal(sent, 1, "Ctrl+Enter must not submit");
+    assert.ok(textarea.value.includes("\n"), "Ctrl+Enter should insert a newline");
+    b._panel.remove();
+  });
+
+  // ── 9. General assistant action blocks ──
+  await test("_extractActions parses obsigate-action blocks", () => {
+    const b = new BooksLM();
+    const raw = 'Je crée le fichier.\n```obsigate-action\n{"action":"create_file","vault":"V","path":"a.md","content":"# A"}\n```';
+    const { text, actions } = b._extractActions(raw);
+    assert.equal(actions.length, 1);
+    assert.equal(actions[0].action, "create_file");
+    assert.equal(actions[0].path, "a.md");
+    assert.ok(!text.includes("obsigate-action"), "action block removed from display text");
+  });
+
+  await test("_extractActions ignores malformed blocks", () => {
+    const b = new BooksLM();
+    const { text, actions } = b._extractActions("```obsigate-action\nnot json\n```");
+    assert.equal(actions.length, 0);
+    assert.ok(text.length >= 0);
+  });
+
+  // ── 10. Header ergonomics: actions always visible, picker on its own row ──
+  await test("assistant header exposes context, actions and a picker row", () => {
+    const b = new BooksLM();
+    const panel = b._render();
+    const actions = panel.querySelector(".bookslm-header-actions");
+    assert.ok(actions, "header actions container");
+    assert.ok(actions.querySelector(".bookslm-btn-new"));
+    assert.ok(actions.querySelector(".bookslm-btn-export"));
+    assert.ok(actions.querySelector(".bookslm-btn-fullscreen"));
+    assert.ok(actions.querySelector(".bookslm-btn-close"));
+    assert.ok(panel.querySelector(".bookslm-toolbar .bookslm-picker-host"), "picker on its own toolbar row");
+    assert.ok(panel.querySelector(".bookslm-input-hint"), "keyboard hint shown");
+    panel.remove();
+  });
+
   // ── Summary ──
   console.log(`\n${passCount}/${testCount} tests passed`);
   if (passCount !== testCount) {
     process.exit(1);
-  }
-}
+  }}
 
 main().catch((e) => {
   console.error(e);

tests/frontend/unit.test.mjs

@@ -195,7 +195,7 @@ function testAIFabModuleExists() {
   const content = readFileSync(AIFAB_PATH, 'utf-8');
   assert.ok(content.length > 0, 'ai-fab.js must be a non-empty file');
   assert.ok(/from\s+['"]\.\/bookslm\.js['"]/.test(content), 'ai-fab.js must import from ./bookslm.js');
-  assert.ok(/from\s+['"]\.\/state\.js['"]/.test(content), 'ai-fab.js must import from ./state.js');
+  assert.ok(/from\s+['"]\.\/utils\.js['"]/.test(content), 'ai-fab.js must import from ./utils.js');
   assert.ok(/from\s+['"]\.\/i18n\.js['"]/.test(content), 'ai-fab.js must import from ./i18n.js');
   console.log('  ✓ ai-fab.js exists and imports the expected modules');
 }