fix(desktop): resolve PortableGit for update checks + reserve titlebar tools space

- runGit() hardcoded spawn('git'), which ENOENTs on fresh installer-driven
  Windows installs (git is PortableGit under %LOCALAPPDATA%\hermes\git, never
  on PATH) — so "Check for updates" failed with "Couldn't check for updates".
  Add resolveGitBinary() mirroring findGitBash (PortableGit → Git-for-Windows
  → PATH) and use it in runGit.
- PageSearchShell rendered a full-width search input in the titlebar row, so
  on Windows its right edge slid under the fixed top-right tools + native
  window controls. Reserve that footprint via --titlebar-tools-* vars.

apps/desktop/electron/main.cjs

@@ -926,6 +926,35 @@ function getVenvPython(venvRoot) {
   return path.join(venvRoot, IS_WINDOWS ? path.join('Scripts', 'python.exe') : path.join('bin', 'python'))
 }
 
+// resolveGitBinary — locate git.exe on Windows. A fresh installer-driven
+// install only has PortableGit under %LOCALAPPDATA%\hermes\git (never on
+// PATH), so a bare spawn('git') ENOENTs and self-update checks fail with
+// "Couldn't check for updates". Mirror findGitBash: PortableGit first, then
+// standard Git-for-Windows locations, then PATH. Cached after first probe.
+let _gitBinaryCache = null
+function resolveGitBinary() {
+  if (_gitBinaryCache) return _gitBinaryCache
+  if (!IS_WINDOWS) {
+    _gitBinaryCache = findOnPath('git') || 'git'
+    return _gitBinaryCache
+  }
+
+  const localAppData = process.env.LOCALAPPDATA || ''
+  const candidates = []
+  if (localAppData) {
+    candidates.push(path.join(localAppData, 'hermes', 'git', 'cmd', 'git.exe'))
+    candidates.push(path.join(localAppData, 'hermes', 'git', 'bin', 'git.exe'))
+  }
+  candidates.push(path.join(process.env['ProgramFiles'] || 'C:\\Program Files', 'Git', 'cmd', 'git.exe'))
+  candidates.push(path.join(process.env['ProgramFiles(x86)'] || 'C:\\Program Files (x86)', 'Git', 'cmd', 'git.exe'))
+  if (localAppData) {
+    candidates.push(path.join(localAppData, 'Programs', 'Git', 'cmd', 'git.exe'))
+  }
+
+  _gitBinaryCache = candidates.find(fileExists) || findOnPath('git') || 'git'
+  return _gitBinaryCache
+}
+
 function recentHermesLog() {
   return hermesLog.slice(-20).join('\n')
 }
@@ -962,7 +991,7 @@ function resolveUpdateRoot() {
 
 function runGit(args, options = {}) {
   return new Promise((resolve, reject) => {
-    const child = spawn('git', IS_WINDOWS ? ['-c', 'windows.appendAtomically=false', ...args] : args, {
+    const child = spawn(resolveGitBinary(), IS_WINDOWS ? ['-c', 'windows.appendAtomically=false', ...args] : args, {
       cwd: options.cwd,
       env: { ...process.env, ...(options.env || {}), GIT_TERMINAL_PROMPT: '0' },
       stdio: ['ignore', 'pipe', 'pipe']

apps/desktop/src/app/page-search-shell.tsx

@@ -29,12 +29,22 @@ export function PageSearchShell({
       className={cn('flex h-full min-w-0 flex-col overflow-hidden bg-(--ui-chat-surface-background)', className)}
     >
       <div className="relative z-10 grid gap-2 border-b border-(--ui-stroke-tertiary) px-3 py-2.5">
-        <PageSearchInput
-          onChange={onSearchChange}
-          placeholder={searchPlaceholder}
-          trailingAction={searchTrailingAction}
-          value={searchValue}
-        />
+        {/* Reserve the top-right titlebar tools + native window-controls
+            footprint so the full-width search input never slides under them
+            (this header sits in the titlebar row at the window top). */}
+        <div
+          style={{
+            paddingRight:
+              'max(0px, calc(var(--titlebar-tools-right, 0px) + var(--titlebar-tools-width, 0px) - 0.75rem))'
+          }}
+        >
+          <PageSearchInput
+            onChange={onSearchChange}
+            placeholder={searchPlaceholder}
+            trailingAction={searchTrailingAction}
+            value={searchValue}
+          />
+        </div>
         {filters ? <div className="flex flex-wrap items-center justify-center gap-1.5">{filters}</div> : null}
       </div>
       <div className="min-h-0 flex-1 overflow-hidden bg-(--ui-chat-surface-background)">{children}</div>