style(codex): use monochrome sidebar icon

- add a dedicated monochrome Codex sidebar asset

- keep the existing colored Codex icons unchanged elsewhere

ui/public/assets/sidebar/codex.svg

@@ -0,0 +1 @@
+<svg fill="currentColor" fill-rule="evenodd" height="1em" style="flex:none;line-height:1" viewBox="0 0 24 24" width="1em" xmlns="http://www.w3.org/2000/svg"><title>Codex</title><path clip-rule="evenodd" d="M8.086.457a6.105 6.105 0 013.046-.415c1.333.153 2.521.72 3.564 1.7a.117.117 0 00.107.029c1.408-.346 2.762-.224 4.061.366l.063.03.154.076c1.357.703 2.33 1.77 2.918 3.198.278.679.418 1.388.421 2.126a5.655 5.655 0 01-.18 1.631.167.167 0 00.04.155 5.982 5.982 0 011.578 2.891c.385 1.901-.01 3.615-1.183 5.14l-.182.22a6.063 6.063 0 01-2.934 1.851.162.162 0 00-.108.102c-.255.736-.511 1.364-.987 1.992-1.199 1.582-2.962 2.462-4.948 2.451-1.583-.008-2.986-.587-4.21-1.736a.145.145 0 00-.14-.032c-.518.167-1.04.191-1.604.185a5.924 5.924 0 01-2.595-.622 6.058 6.058 0 01-2.146-1.781c-.203-.269-.404-.522-.551-.821a7.74 7.74 0 01-.495-1.283 6.11 6.11 0 01-.017-3.064.166.166 0 00.008-.074.115.115 0 00-.037-.064 5.958 5.958 0 01-1.38-2.202 5.196 5.196 0 01-.333-1.589 6.915 6.915 0 01.188-2.132c.45-1.484 1.309-2.648 2.577-3.493.282-.188.55-.334.802-.438.286-.12.573-.22.861-.304a.129.129 0 00.087-.087A6.016 6.016 0 015.635 2.31C6.315 1.464 7.132.846 8.086.457zm-.804 7.85a.848.848 0 00-1.473.842l1.694 2.965-1.688 2.848a.849.849 0 001.46.864l1.94-3.272a.849.849 0 00.007-.854l-1.94-3.393zm5.446 6.24a.849.849 0 000 1.695h4.848a.849.849 0 000-1.696h-4.848z"></path></svg>

ui/src/components/layout/app-sidebar.tsx

@@ -119,7 +119,7 @@ function buildNavGroups(t: (key: string) => string): SidebarGroupDef[] {
       title: t('nav.compatibleClis'),
       items: [
         { path: '/claude-extension', icon: Puzzle, label: t('nav.claudeExtension') },
-        { path: '/codex', iconSrc: '/assets/providers/codex-color.svg', label: 'Codex CLI' },
+        { path: '/codex', iconSrc: '/assets/sidebar/codex.svg', label: 'Codex CLI' },
         { path: '/droid', icon: TerminalSquare, label: t('nav.factoryDroid') },
       ],
     },