fix: Ralph wizard uses file-based prompt to avoid screen escaping issues

- Add /api/sessions/:id/ralph-prompt/write endpoint to write prompt to @ralph_prompt.md
- Wizard now writes full prompt to file, then sends simple read command to Claude
- Fix session readiness check to wait for prompt character instead of notWorking flag
- Add E2E test infrastructure for ralph-loop workflow (port 3190)
- Add ralph-wizard-prod.mjs script for production testing

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/web/public/index.html

@@ -1081,10 +1081,10 @@
                 <div class="form-row form-row-switch">
                   <label>Enable Respawn</label>
                   <label class="switch">
-                    <input type="checkbox" id="ralphEnableRespawn" checked>
+                    <input type="checkbox" id="ralphEnableRespawn">
                     <span class="slider"></span>
                   </label>
-                  <span class="form-hint">Auto-restart sessions when context fills up</span>
+                  <span class="form-hint">Auto-restart sessions when context fills up (usually not needed)</span>
                 </div>
               </div>
             </details>