feat: Redesign New Chat (#31)

* make subject is optional

* redesign

* search

* fix

* adjust

crates/ui/src/icon.rs

@@ -54,6 +54,7 @@ pub enum IconName {
     PanelRightClose,
     PanelRightOpen,
     Plus,
+    PlusFill,
     PlusCircleFill,
     Relays,
     ResizeCorner,
@@ -124,6 +125,7 @@ impl IconName {
             Self::PanelRightClose => "icons/panel-right-close.svg",
             Self::PanelRightOpen => "icons/panel-right-open.svg",
             Self::Plus => "icons/plus.svg",
+            Self::PlusFill => "icons/plus-fill.svg",
             Self::PlusCircleFill => "icons/plus-circle-fill.svg",
             Self::Relays => "icons/relays.svg",
             Self::ResizeCorner => "icons/resize-corner.svg",