Research: add configurable run timeout

Surfaces the research_run_timeout_seconds setting (added in #783) in
Settings → Research as a "Max Time" field, and lets 0 disable the
wall-clock cap entirely for long deep-research runs.

- settings.py: document that 0 disables the cap; default stays 1800s.
- research_handler.py: resolve 0 (or negative) to no timeout
  (asyncio.wait_for timeout=None); other values stay bounded to
  [60, 86400] as before.
- index.html / settings.js: "Max Time" input bound to
  research_run_timeout_seconds, validated to {0} ∪ [60, 86400], with
  copy making explicit that 0 = no limit (unbounded model/API cost).

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

static/index.html

@@ -1463,6 +1463,10 @@
                 <label class="settings-label">Extract Parallel</label>
                 <input id="set-researchExtractConcurrency" type="text" inputmode="numeric" placeholder="3" class="settings-select" style="width:120px;">
               </div>
+              <div class="settings-row">
+                <label class="settings-label">Max Time</label>
+                <input id="set-researchRunTimeout" type="text" inputmode="numeric" placeholder="1800 sec (0 = no limit)" class="settings-select" style="width:120px;">
+              </div>
               <div id="set-researchMsg" style="font-size:11px;color:color-mix(in srgb, var(--fg) 45%, transparent);"></div>
             </div>
           </div>

static/js/settings.js

@@ -1402,6 +1402,7 @@ async function initResearchSettings() {
   var tokensInput = el('set-researchMaxTokens');
   var extractTimeoutInput = el('set-researchExtractTimeout');
   var extractConcurrencyInput = el('set-researchExtractConcurrency');
+  var runTimeoutInput = el('set-researchRunTimeout');
   var msg = el('set-researchMsg');
   var endpoints = [];
 
@@ -1424,6 +1425,9 @@ async function initResearchSettings() {
     if (settings.research_max_tokens) tokensInput.value = settings.research_max_tokens;
     if (settings.research_extraction_timeout_seconds) extractTimeoutInput.value = settings.research_extraction_timeout_seconds;
     if (settings.research_extraction_concurrency) extractConcurrencyInput.value = settings.research_extraction_concurrency;
+    if (settings.research_run_timeout_seconds !== undefined && settings.research_run_timeout_seconds !== null) {
+      runTimeoutInput.value = settings.research_run_timeout_seconds;
+    }
   } catch (e) { console.warn('Failed to load research settings', e); }
 
   function showStatus() {
@@ -1442,6 +1446,12 @@ async function initResearchSettings() {
     if (extractConcurrencyInput.value) {
       parts.push('Parallel: ' + extractConcurrencyInput.value);
     }
+    if (runTimeoutInput.value !== '') {
+      var rtv = parseInt(runTimeoutInput.value, 10);
+      if (!isNaN(rtv)) {
+        parts.push(rtv === 0 ? 'Max time: no limit' : 'Max time: ' + rtv + 's');
+      }
+    }
     if (parts.length) {
       msg.textContent = parts.join(' · ');
       msg.style.color = 'var(--fg)';
@@ -1463,6 +1473,13 @@ async function initResearchSettings() {
     if (et && et >= 15 && et <= 3600) payload.research_extraction_timeout_seconds = et;
     var ec = parseInt(extractConcurrencyInput.value, 10);
     if (ec && ec >= 1 && ec <= 12) payload.research_extraction_concurrency = ec;
+    if (runTimeoutInput.value !== '') {
+      var rt = parseInt(runTimeoutInput.value, 10);
+      // 0 = no limit (disables the hard timeout); otherwise 60s..86400s (24h)
+      if (!isNaN(rt) && (rt === 0 || (rt >= 60 && rt <= 86400))) {
+        payload.research_run_timeout_seconds = rt;
+      }
+    }
     try {
       await fetch('/api/auth/settings', { method: 'POST', credentials: 'same-origin',
         headers: { 'Content-Type': 'application/json' },
@@ -1481,6 +1498,7 @@ async function initResearchSettings() {
   tokensInput.addEventListener('change', saveResearch);
   extractTimeoutInput.addEventListener('change', saveResearch);
   extractConcurrencyInput.addEventListener('change', saveResearch);
+  runTimeoutInput.addEventListener('change', saveResearch);
 
   _registerAiEndpointRefresh(function(nextEndpoints) {
     endpoints = nextEndpoints;