release: restore prose-level fade for Transparent Stream (#5506)

Re-adds the per-word prose fade for newly-streamed assistant text in Transparent Stream WITHOUT reintroducing the row-level entrance flicker (#5367). Reduced-motion honored at both JS and CSS layers; thinking/tool rows not animated. Option A: the fade is part of Transparent Stream regardless of the off-by-default 'Fade text effect' toggle; settings description clarified accordingly. Gate: Codex SAFE, Fable SHIP-UX, suite 12158/0, browser-smoke clean.

Co-authored-by: Rod Boev <rod.boev@gmail.com>

CHANGELOG.md

@@ -9,6 +9,7 @@
 
 ### Added
 
+- **Transparent Stream fades newly streamed words in.** In Transparent Stream mode, newly arriving assistant words now fade in at the prose level as they stream — without animating (or re-flickering) the thinking rows, tool rows, or the transparent event rows. It respects your OS "reduce motion" setting (no fade when reduced motion is on) and is part of the Transparent Stream experience regardless of the "Fade text effect" toggle. Thanks @rodboev. (#5506, #5367)
 - **The Preferences default-model setting now uses the rich model picker.** The "Default Model" control in Settings → Preferences was a plain dropdown; it now uses the same searchable, provider-grouped picker as the composer (with a "Custom Model ID" field), so choosing a default model is consistent everywhere. On touch devices the picker no longer pops the keyboard the instant you open it (it still focuses search on desktop and while you're typing), and its label now activates the picker directly. Thanks @rodboev. (#5502, #5497)
 - **Scheduled jobs get a preset schedule builder.** The cron job form now has a "Preset" dropdown (Hourly / Daily / Weekdays / Weekly / Monthly, plus Custom) above the Schedule field — pick one and it fills the schedule for you (e.g. Daily → `0 9 * * *`, Hourly → `every 1h`) instead of hand-writing a cron expression. "Custom" keeps the free-text field, and editing an existing job maps its schedule back to the matching preset. Thanks @rodboev. (#5438, #5427)
 - **Add a self-hosted provider (Ollama or LM Studio) from Settings.** After onboarding, a new Settings control lets you point WebUI at a local OpenAI-compatible model server (Ollama / LM Studio) by choosing the provider, model, and base URL — no hand-editing `config.yaml`. The base URL is validated (scheme + provider allowlist) and persisted for the agent's provider client. An optional "Test connection" button reuses the existing authenticated onboarding probe to fetch the model list from the URL you enter. Thanks @rodboev. (#5408, #3260)

static/index.html

@@ -1293,7 +1293,7 @@
                 <input type="checkbox" id="settingsFadeTextEffect" style="width:15px;height:15px;accent-color:var(--accent)">
                 <span data-i18n="settings_label_fade_text_effect">Fade text effect</span>
               </label>
-              <div style="font-size:11px;color:var(--muted);margin-top:4px" data-i18n="settings_desc_fade_text_effect">Fade newly streamed words in while the assistant is responding. Similar to OpenWebUI; off by default for maximum performance.</div>
+              <div style="font-size:11px;color:var(--muted);margin-top:4px" data-i18n="settings_desc_fade_text_effect">Fade newly streamed words in while the assistant is responding. Similar to OpenWebUI; off by default for maximum performance. Transparent Stream always fades prose as part of that mode, regardless of this setting.</div>
             </div>
             <div class="settings-field">
               <label style="display:flex;align-items:center;gap:8px;cursor:pointer">