feat: hand off assigned issues from mobile (#281)

frontend/index.html

@@ -189,6 +189,10 @@ textarea { resize: vertical; min-height: 120px; }
 .issue-sheet-actions { position:sticky; bottom:0; z-index:3; display:grid; gap:8px; margin-top:14px; padding:10px 4px; padding-bottom:calc(10px + env(safe-area-inset-bottom)); background:rgba(11,21,38,.98); border-top:1px solid #2a496e; }
 .issue-sheet-actions button, .issue-sheet-actions a { min-height:44px; display:flex; align-items:center; justify-content:center; }
 .issue-sheet-actions a { border:1px solid #60a5fa; border-radius:10px; font-weight:700; }
+.issue-handoff { margin-top:14px; padding:12px; border:1px solid #2a496e; border-radius:12px; }
+.issue-handoff > div { display:grid; gap:8px; margin-top:10px; }
+.issue-handoff select { width:100%; max-width:100%; padding:8px; border:1px solid #1f3a5f; border-radius:8px; background:#0b1526; color:var(--text); }
+.issue-handoff select, .issue-handoff button { min-height:44px; }
 .issue-retry { min-height:44px; width:100%; margin-top:10px; }
 .new-issue { min-height:44px; }
 .find-work-action { min-height:44px; }
@@ -519,6 +523,16 @@ textarea { resize: vertical; min-height: 120px; }
         <div id="issue-milestone-status" class="small" aria-live="assertive">Expand planning controls to load milestones.</div>
       </fieldset>
     </details>
+    <details class="issue-handoff" id="issue-handoff">
+      <summary>Hand off to teammate</summary>
+      <div>
+        <button id="load-issue-handoff" type="button">Choose teammate</button>
+        <label for="issue-handoff-recipient" class="small">Eligible repository assignee</label>
+        <select id="issue-handoff-recipient" disabled><option value="">Select a teammate</option></select>
+        <button id="confirm-issue-handoff" type="button" disabled>Confirm handoff</button>
+        <div id="issue-handoff-status" class="small" aria-live="assertive">Load teammates to transfer ownership.</div>
+      </div>
+    </details>
     <div class="issue-sheet-actions">
       <button class="share-work-route" type="button">Share</button>
       <button id="release-issue" type="button">Release assignment</button>
@@ -1803,6 +1817,12 @@ textarea { resize: vertical; min-height: 120px; }
     qs('#issue-conversation-status').textContent = 'Loading newest messages…';
     qs('#issue-comment').value = issueController.loadDraft(item);
     qs('#issue-comment-status').textContent = '';
+    qs('#issue-handoff').open = false;
+    qs('#issue-handoff-recipient').innerHTML = '<option value="">Select a teammate</option>';
+    qs('#issue-handoff-recipient').disabled = true;
+    qs('#confirm-issue-handoff').disabled = true;
+    qs('#load-issue-handoff').disabled = false;
+    qs('#issue-handoff-status').textContent = 'Load teammates to transfer ownership.';
     qs('#issue-planning').open = false;
     qs('#retry-issue-planning').hidden = true;
     qs('#issue-label-list').textContent = '';
@@ -3130,6 +3150,60 @@ textarea { resize: vertical; min-height: 120px; }
       button.focus();
     }
   });
+  qs('#load-issue-handoff').addEventListener('click', async () => {
+    if (!selectedIssue) return;
+    const button = qs('#load-issue-handoff');
+    const select = qs('#issue-handoff-recipient');
+    button.disabled = true;
+    qs('#issue-handoff-status').textContent = 'Loading eligible teammates…';
+    try {
+      const candidates = await issueController.loadHandoffCandidates(selectedIssue);
+      select.textContent = '';
+      const placeholder = document.createElement('option');
+      placeholder.value = '';
+      placeholder.textContent = candidates.length ? 'Select a teammate' : 'No eligible teammates';
+      select.appendChild(placeholder);
+      candidates.forEach(candidate => {
+        const option = document.createElement('option');
+        option.value = candidate.login;
+        option.textContent = candidate.name + (candidate.name === candidate.login ? '' : ' (@' + candidate.login + ')');
+        select.appendChild(option);
+      });
+      select.disabled = !candidates.length;
+      qs('#confirm-issue-handoff').disabled = true;
+      qs('#issue-handoff-status').textContent = candidates.length ?
+        'Choose who should own this issue next.' : 'No other eligible assignees were found.';
+      if (candidates.length) select.focus();
+    } catch (error) {
+      qs('#issue-handoff-status').textContent = error.message + ' Retry loading teammates.';
+      button.disabled = false;
+      button.focus();
+    }
+  });
+  qs('#issue-handoff-recipient').addEventListener('change', event => {
+    qs('#confirm-issue-handoff').disabled = !event.target.value;
+  });
+  qs('#confirm-issue-handoff').addEventListener('click', async () => {
+    const recipient = qs('#issue-handoff-recipient').value;
+    if (!selectedIssue || !recipient || !window.confirm('Hand off ' + selectedIssue.key + ' to @' + recipient + '?')) return;
+    const handingOff = selectedIssue;
+    const button = qs('#confirm-issue-handoff');
+    button.disabled = true;
+    qs('#issue-handoff-status').textContent = 'Confirming handoff…';
+    try {
+      await issueController.handoff(selectedIssue, recipient, lastContextSnapshot?.user?.login);
+      lastContextSnapshot = buildMyWork.removeIssue(
+        lastContextSnapshot, handingOff.repository, handingOff.number
+      );
+      closeIssueSheet();
+      paintMyWork(lastContextSnapshot);
+      qs('#my-work-action-status').textContent = handingOff.key + ' handed off to @' + recipient + '.';
+    } catch (error) {
+      qs('#issue-handoff-status').textContent = error.message + ' The issue remains in My Work; retry.';
+      button.disabled = false;
+      button.focus();
+    }
+  });
   qs('#close-issue').addEventListener('click', async () => {
     if (!selectedIssue || !window.confirm('Close ' + selectedIssue.key + '?')) return;
     const closing = selectedIssue;

frontend/issue-sheet.js

@@ -22,6 +22,7 @@ function createIssueSheet({ fetchJson, storage, createConversationPager = global
   let commentRequest = null;
   let closeRequest = null;
   let releaseRequest = null;
+  let handoffRequest = null;
   let labelRequest = null;
   let editRequest = null;
   let dueDateRequest = null;
@@ -61,6 +62,11 @@ function createIssueSheet({ fetchJson, storage, createConversationPager = global
         headers: { Accept: 'application/json' },
       });
     },
+    loadHandoffCandidates(item) {
+      return fetchJson(issuePath(item) + '/handoff-candidates', {
+        headers: { Accept: 'application/json' },
+      });
+    },
     loadDraft(item) {
       try { return storage?.getItem(draftKey(item)) || ''; }
       catch (_error) { return ''; }
@@ -209,6 +215,26 @@ function createIssueSheet({ fetchJson, storage, createConversationPager = global
       }).finally(() => { releaseRequest = null; });
       return releaseRequest;
     },
+    handoff(item, recipient, currentLogin) {
+      if (handoffRequest) return handoffRequest;
+      handoffRequest = fetchJson(issuePath(item) + '/handoff', {
+        method: 'PATCH',
+        headers: { Accept: 'application/json', 'Content-Type': 'application/json' },
+        body: JSON.stringify({ recipient }),
+      }).then(result => {
+        if (
+          result?.number !== item.number ||
+          result?.recipient !== recipient ||
+          !Array.isArray(result.assignees) ||
+          !result.assignees.includes(recipient) ||
+          result.assignees.includes(currentLogin)
+        ) {
+          throw new Error('Issue handoff was not confirmed.');
+        }
+        return result;
+      }).finally(() => { handoffRequest = null; });
+      return handoffRequest;
+    },
     comment(item, body) {
       if (commentRequest) return commentRequest;
       this.saveDraft(item, body);

frontend/service-worker.js

@@ -1,6 +1,6 @@
 const BASE = new URL('./', self.location.href).pathname;
 importScripts(BASE + 'static/background-issue-sync.js');
-const CACHE = 'stackchain-dashboard-shell-v20';
+const CACHE = 'stackchain-dashboard-shell-v21';
 const OUTAGE_STATUSES = new Set([500, 502, 503, 504]);
 const SHELL = [
   BASE,