tui: improve modified file visibility and button spacing

- Replace warning yellow with distinct orange color for modified files in git diff indicators
- Increase button padding for better visual balance in session header and status popover

packages/app/src/components/file-tree.tsx

@@ -71,13 +71,13 @@ const kindLabel = (kind: Kind) => {
 const kindTextColor = (kind: Kind) => {
   if (kind === "add") return "color: var(--icon-diff-add-base)"
   if (kind === "del") return "color: var(--icon-diff-delete-base)"
-  return "color: var(--icon-warning-active)"
+  return "color: var(--icon-diff-modified-base)"
 }
 
 const kindDotColor = (kind: Kind) => {
   if (kind === "add") return "background-color: var(--icon-diff-add-base)"
   if (kind === "del") return "background-color: var(--icon-diff-delete-base)"
-  return "background-color: var(--icon-warning-active)"
+  return "background-color: var(--icon-diff-modified-base)"
 }
 
 const visibleKind = (node: FileNode, kinds?: ReadonlyMap<string, Kind>, marks?: Set<string>) => {

packages/app/src/components/session/session-header.tsx

@@ -354,7 +354,7 @@ export function SessionHeader() {
                       <div class="flex h-[24px] box-border items-center rounded-md border border-border-weak-base bg-surface-panel overflow-hidden">
                         <Button
                           variant="ghost"
-                          class="rounded-none h-full py-0 pr-2 pl-0.5 gap-1.5 border-none shadow-none"
+                          class="rounded-none h-full py-0 pr-3 pl-0.5 gap-1.5 border-none shadow-none"
                           onClick={copyPath}
                           aria-label={language.t("session.header.open.copyPath")}
                         >

packages/app/src/components/status-popover.tsx

@@ -196,7 +196,7 @@ export function StatusPopover() {
       triggerProps={{
         variant: "ghost",
         class:
-          "rounded-md h-[24px] pr-2 pl-0.5 gap-2 border border-border-weak-base bg-surface-panel shadow-none data-[expanded]:bg-surface-raised-base-hover",
+          "rounded-md h-[24px] pr-3 pl-0.5 gap-2 border border-border-weak-base bg-surface-panel shadow-none data-[expanded]:bg-surface-raised-base-hover",
         style: { scale: 1 },
       }}
       trigger={