Add update.sh, release-channel tagging, mobile settings page

install.sh / install-nightly.sh:
  - Write .release-channel file ('release' or 'nightly') for future updates
  - install.sh also writes .release-version (for update --check)

update.sh (new):
  - Reads .release-channel to determine which channel to pull from
  - Release: checks releases/LATEST vs .release-version, skips if current
  - Nightly: always downloads latest
  - Stops service before extraction, restarts after
  - Rebuilds Python venv on update

ci/package.sh:
  - Include update.sh in distribution tarball

Web / mobile:
  - Add settings-page component for mobile
  - Wire settings page into mobile-app navigation
  - Chat page: load current user (/api/auth/me) for sender identity
  - Full mobile.css redesign
  - i18n: add mobile settings strings (en/fr/it)

web/components/shared/chat-page.js

@@ -12,6 +12,7 @@ export class ChatPage extends ChatSession {
     // Human-readable label for the active source (e.g. the project name), shown
     // in the header when inside a project.
     label:   { type: String },
+    _me:     { state: true },
   };
 
   constructor() {
@@ -19,6 +20,14 @@ export class ChatPage extends ChatSession {
     this.visible = false;
     this.source  = 'mobile';
     this.label   = '';
+    this._me     = null;
+  }
+
+  async _loadMe() {
+    try {
+      const res = await fetch('/api/auth/me');
+      if (res.ok) this._me = await res.json();
+    } catch { /* greeting falls back to the generic one */ }
   }
 
   connectedCallback() {
@@ -29,6 +38,7 @@ export class ChatPage extends ChatSession {
     // still handled by `updated` below.
     if (this.source && this.source !== this._wsSource) this._activeSource = this.source;
     super.connectedCallback();
+    this._loadMe();
   }
 
   updated(changed) {
@@ -95,6 +105,49 @@ export class ChatPage extends ChatSession {
     this._expanded = next;
   }
 
+  _sendSuggestion(text) {
+    const el = this._inputEl();
+    if (!el) return;
+    el.value = text;
+    this._send();
+  }
+
+  // Welcome hero (main session) with a few prompt suggestions, mirroring the
+  // desktop home. Inside a project the empty state stays compact — the header
+  // already carries the context.
+  _renderEmptyState() {
+    if (this._inProject) {
+      return html`
+        <div class="chat-page-hero">
+          <i class="bi bi-folder2-open" style="font-size:1.6rem;color:var(--accent)"></i>
+          <p class="chat-page-hero-sub" style="margin:0.5rem 0 0">${this.label || t('chat.mobile.project')}</p>
+        </div>
+      `;
+    }
+    const name = this._me?.display_name || this._me?.username;
+    const suggestions = [
+      { icon: 'bi-stars',          text: t('chat.suggest.1') },
+      { icon: 'bi-calendar-check', text: t('chat.suggest.2') },
+      { icon: 'bi-book',           text: t('chat.suggest.3') },
+      { icon: 'bi-heart',          text: t('chat.suggest.4') },
+    ];
+    return html`
+      <div class="chat-page-hero">
+        <img class="chat-page-hero-logo" src="/assets/icons/icon-192.png" alt="" />
+        <h1 class="chat-page-hero-title">${name ? t('chat.greeting.named', { name }) : t('chat.greeting')}</h1>
+        <p class="chat-page-hero-sub">${t('chat.greeting.sub')}</p>
+        <div class="chat-page-suggestions">
+          ${suggestions.map(s => html`
+            <button class="chat-page-suggestion" @click=${() => this._sendSuggestion(s.text)}>
+              <i class="bi ${s.icon}"></i>
+              <span>${s.text}</span>
+            </button>
+          `)}
+        </div>
+      </div>
+    `;
+  }
+
   // ── Render ─────────────────────────────────────────────────────────────────
 
   render() {
@@ -123,12 +176,7 @@ export class ChatPage extends ChatSession {
         </div>
 
         <div class="chat-page-messages">
-          ${this._messages.length === 0 ? html`
-            <div class="chat-page-empty">
-              <i class="bi bi-stars"></i>
-              <p>${t('chat.mobile.ask')}</p>
-            </div>
-          ` : this._messages.map(m => renderMsg(this, m))}
+          ${this._messages.length === 0 ? this._renderEmptyState() : this._messages.map(m => renderMsg(this, m))}
 
           ${this._waiting ? html`
             <div class="copilot-msg assistant copilot-thinking">

web/components/shared/settings-page.js

@@ -0,0 +1,126 @@
+import { html, nothing } from 'lit';
+import { LightElement }  from '../../lib/base.js';
+import { t, LOCALES, getLocale, setLocale, I18nMixin } from '../../lib/i18n.js';
+
+// Stable per-user avatar color: same user, same hue, everywhere (topbar twin).
+function avatarColor(name) {
+  let h = 0;
+  for (let i = 0; i < name.length; i++) h = (h * 31 + name.charCodeAt(i)) >>> 0;
+  return `hsl(${h % 360}, 55%, 52%)`;
+}
+
+/**
+ * Mobile settings page: account card, theme + language preferences and logout.
+ * The theme chain mirrors the desktop topbar (localStorage `theme` wins over
+ * the OS preference, applied on `data-bs-theme`); the language goes through
+ * the shared `setLocale(..., { persist: true })`, which also saves it to the
+ * user profile server-side.
+ */
+export class SettingsPage extends I18nMixin(LightElement) {
+  static properties = {
+    visible: { type: Boolean },
+    _me:     { state: true },
+    _theme:  { state: true },
+  };
+
+  constructor() {
+    super();
+    this.visible = false;
+    this._me     = null;
+    this._theme  = document.documentElement.getAttribute('data-bs-theme') ?? 'light';
+  }
+
+  updated(changed) {
+    if (changed.has('visible') && this.visible) this._loadMe();
+  }
+
+  async _loadMe() {
+    try {
+      const res = await fetch('/api/auth/me');
+      if (res.ok) this._me = await res.json();
+    } catch { /* keep whatever we have */ }
+  }
+
+  _setTheme(theme) {
+    this._theme = theme;
+    document.documentElement.setAttribute('data-bs-theme', theme);
+    localStorage.setItem('theme', theme);
+  }
+
+  _setLocale(e) {
+    setLocale(e.target.value, { persist: true });
+  }
+
+  _logout() {
+    fetch('/api/auth/logout', { method: 'POST' }).then(() => window.location.reload());
+  }
+
+  render() {
+    if (!this.visible) return nothing;
+
+    const name    = this._me?.display_name || this._me?.username || '';
+    const initial = name ? name.charAt(0).toUpperCase() : '?';
+    const color   = this._me?.username ? avatarColor(this._me.username) : 'var(--accent)';
+    const current = getLocale();
+
+    return html`
+      <div class="mobile-settings">
+        <div class="mobile-section-header">
+          <span class="mobile-section-title">
+            <i class="bi bi-sliders"></i> ${t('mobile.nav.settings')}
+          </span>
+        </div>
+
+        <div class="mobile-settings-scroll">
+          <div class="settings-card">
+            <div class="settings-profile">
+              <div class="settings-avatar" style="background:${color}">${initial}</div>
+              <div>
+                <div class="settings-profile-name">${name}</div>
+                <div class="settings-profile-sub">@${this._me?.username ?? ''}</div>
+              </div>
+            </div>
+          </div>
+
+          <div class="settings-card">
+            <div class="settings-row">
+              <span class="settings-row-label">
+                <i class="bi ${this._theme === 'dark' ? 'bi-moon-stars' : 'bi-sun'}"></i>
+                ${t('mobile.settings.theme')}
+              </span>
+              <div class="settings-segment">
+                <button class="${this._theme === 'light' ? 'active' : ''}"
+                        title=${t('mobile.settings.light')}
+                        @click=${() => this._setTheme('light')}>
+                  <i class="bi bi-sun"></i>
+                </button>
+                <button class="${this._theme === 'dark' ? 'active' : ''}"
+                        title=${t('mobile.settings.dark')}
+                        @click=${() => this._setTheme('dark')}>
+                  <i class="bi bi-moon-stars"></i>
+                </button>
+              </div>
+            </div>
+            <div class="settings-row">
+              <span class="settings-row-label">
+                <i class="bi bi-translate"></i>
+                ${t('mobile.settings.language')}
+              </span>
+              <select class="settings-lang-select" @change=${(e) => this._setLocale(e)}>
+                ${LOCALES.map(l => html`
+                  <option value=${l.id} ?selected=${l.id === current}>${l.label}</option>
+                `)}
+              </select>
+            </div>
+          </div>
+
+          <button class="settings-logout" @click=${() => this._logout()}>
+            <i class="bi bi-box-arrow-right"></i> ${t('topbar.logout')}
+          </button>
+        </div>
+      </div>
+    `;
+  }
+}
+
+customElements.define('settings-page', SettingsPage);