ui: New Logo + Navigation cleanup & Mobile UI/UX improvements (#24897)

* chore: `npm audit fix --force`

* feat: Update sidebar toggle to use Logo

* refactor: Clean up favicon SVG

* feat: Refactor logo component and implement theme-aware favicon generation

* feat: Add configurable padding to generated PWA assets

* test: Add unit tests for writeThemeFavicons

* refactor: Componentization

* feat: WIP

* feat: WIP

* feat: WIP

* feat: Mobile UI

* feat: add SEARCH route constant

* feat: create SidebarNavigationSearchResults component

* refactor: use SidebarNavigationSearchResults in conversation list

* feat: enable mobile search navigation in sidebar actions

* feat: add mobile search route and page

* fix: prevent sidebar overflow on mobile viewports

* fix: Mobile sidebar

* feat: Mobile Search WIP

* feat: Mobile WIP

* feat: Add PWA standalone detection and refine mobile UI

* feat: Improve mobile layout, sidebar handling, and chat scrolling

* feat: Improve mobile sidebar visibility and iOS Safari chat spacing

* fix: Disable auto-scroll on mobile

* chore: Linting

* fix: Wrong condition

* feat: Mobile chat scroll

* refactor: WIP

* fix: Desktop initial scroll always working again

* fix: Partial fix for mobile auto-scroll / initial scroll

* fix: Desktop auto-scroll on initial load and during streaming

* fix: Mobile scrolling logic

* refactor: Clean up

* feat: Improve start UI

* feat: Add `delay` to `fadeInView`

* feat: Auto-scroll button

* refactor: Cleanup

* refactor: Extract chat dialogs and alerts into dedicated component

* refactor: Reorganize ChatScreen component structure and initialization

* feat: Improve auto-scroll after sending message

* feat: UI improvements

* fix: Settings link

* feat: UI improvements

* fix: better UI spacing

* fix: Remove unneeded logic

* fix: Chat Processing Info UI rendering

* feat: Improve mobile UI

* feat: UI improvement

* fix: Conditional transition delay for Chat Messages based on route from

* fix: Delay mobile sidebar collapse for smoother transitions

* fix: Mobile scroll down button + sidebar pointer events

* fix: Mobile UI

* fix: Auto scrolling

* fix: Implement dynamic height calculations for chat auto-scroll positioning and UI elements

* fix: Retrieve `autofocus` for Chat Form textarea

* fix: Use proper class

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* refactor: extract scroll-to-bottom logic and fix message send flow

* fix: update viewport store usage and remove conflicting autofocus

* feat: add accessibility labels to scroll down button

* fix: correct HTML structure in sidebar empty states

* fix: dynamically toggle processing info visibility

* chore: remove commented exports and fix formatting

* fix

* fix: Mobile Chat Form Add Action Sheet interactions

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

tools/ui/src/app.css

@@ -48,6 +48,7 @@
 
 	--chat-form-area-height: 8rem;
 	--chat-form-area-offset: 2rem;
+	--chat-form-padding-top: 6rem;
 	--max-message-height: max(24rem, min(80dvh, calc(100dvh - var(--chat-form-area-height) - 12rem)));
 }
 
@@ -55,6 +56,7 @@
 	:root {
 		--chat-form-area-height: 24rem;
 		--chat-form-area-offset: 12rem;
+		--chat-form-padding-top: 6rem;
 	}
 }
 
@@ -141,7 +143,6 @@
 		@apply bg-background text-foreground;
 		scrollbar-width: thin;
 		scrollbar-gutter: stable;
-		overflow: hidden; /* Added due to Mermaid rendering somehow causing the double scrollbar */
 	}
 
 	/* Global scrollbar styling - visible only on hover */
@@ -193,3 +194,7 @@
 		scrollbar-width: none;
 	}
 }
+
+.mermaidTooltip {
+	display: none !important;
+}