feat: fix tooltip shortcuts and add dev server config dialog

Tooltip fixes (PR #177 follow-up):
- Remove duplicate title attr on Settings button that caused double-tooltip
- Restore keyboard shortcut hints in tooltip text: Settings (,), Reset (R)
- Clean up spurious peer markers in package-lock.json

Dev server config dialog:
- Add DevServerConfigDialog component for custom dev commands
- Open config dialog automatically when start fails with "no dev command"
- Add useDevServerConfig/useUpdateDevServerConfig hooks
- Add updateDevServerConfig API function
- Add config gear button next to dev server start

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ui/src/App.tsx

@@ -302,13 +302,12 @@ function App() {
                         onClick={() => setShowSettings(true)}
                         variant="outline"
                         size="sm"
-                        title="Settings (,)"
                         aria-label="Open Settings"
                       >
                         <Settings size={18} />
                       </Button>
                     </TooltipTrigger>
-                    <TooltipContent>Settings</TooltipContent>
+                    <TooltipContent>Settings (,)</TooltipContent>
                   </Tooltip>
 
                   <Tooltip>
@@ -323,7 +322,7 @@ function App() {
                         <RotateCcw size={18} />
                       </Button>
                     </TooltipTrigger>
-                    <TooltipContent>Reset</TooltipContent>
+                    <TooltipContent>Reset (R)</TooltipContent>
                   </Tooltip>
 
                   {/* Ollama Mode Indicator */}