feat: barre d'outils de lecture epinglee, coloration syntaxique des fichiers de code et avatars predefinis (#115, #117, BUG-078)

frontend/style.css

@@ -1767,7 +1767,22 @@ select {
 
 /* File header */
 .file-header {
-  margin-bottom: 20px;
+  margin-bottom: 8px;
+}
+/* #115 — sticky document action bar: stays visible while long content scrolls.
+   A direct child of `.content-area` (the scroll container), opaque so the text
+   scrolling underneath never bleeds through. */
+.file-toolbar {
+  position: sticky;
+  top: 0;
+  z-index: 30;
+  margin: 0 0 16px;
+  padding: 8px 0;
+  background: var(--bg-primary);
+  border-bottom: 1px solid var(--border);
+}
+.file-toolbar .file-actions {
+  margin-top: 0;
 }
 .file-title {
   font-family: "JetBrains Mono", monospace;
@@ -2670,6 +2685,32 @@ select {
 .profile-avatar-remove-btn { background: var(--danger-bg) !important; color: var(--danger) !important; border-color: var(--danger) !important; }
 .profile-avatar-error { font-size: 0.7rem; color: var(--danger); margin-top: 8px; }
 .profile-avatar-error.hidden { display: none; }
+/* #117 — preset avatar gallery */
+.profile-avatar-presets {
+  display: grid;
+  grid-template-columns: repeat(6, minmax(0, 1fr));
+  gap: 8px;
+  margin-top: 10px;
+  max-width: 420px;
+}
+.profile-avatar-preset {
+  padding: 0;
+  margin: 0;
+  border: 2px solid var(--border);
+  border-radius: 50%;
+  overflow: hidden;
+  cursor: pointer;
+  background: var(--bg-secondary);
+  aspect-ratio: 1;
+  transition: border-color 0.15s ease, box-shadow 0.15s ease, transform 0.1s ease;
+}
+.profile-avatar-preset img { width: 100%; height: 100%; object-fit: cover; display: block; }
+.profile-avatar-preset:hover { border-color: var(--accent); transform: translateY(-1px); }
+.profile-avatar-preset.active {
+  border-color: var(--accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent);
+}
+.profile-avatar-preset:disabled { opacity: 0.6; cursor: progress; }
 .config-save-btn {
   padding: 6px 18px; font-size: 0.75rem; font-weight: 600;
   background: var(--accent); color: #fff;
@@ -4920,6 +4961,11 @@ body.resizing-v {
     flex-wrap: wrap;
     gap: 12px;
   }
+  /* Preset avatars: 4 per row on narrow screens (44px touch targets). */
+  #config-modal .profile-avatar-presets {
+    grid-template-columns: repeat(4, minmax(0, 1fr));
+    max-width: 100%;
+  }
   #config-modal .profile-form {
     max-width: 100%;
   }
@@ -11853,6 +11899,7 @@ body.reading-mode .main-body {
   padding-bottom: 0;
 }
 body.reading-mode .breadcrumb,
+body.reading-mode .file-toolbar,
 body.reading-mode .file-actions {
   display: none;
 }