recover: restore untracked work from recovery branch (no Gemini changes)

Recovered files with no Claude→Agent contamination:
- docs/adr/002-task-state-machine.md
- internal/api/logs.go/logs_test.go: task-level log streaming endpoint
- internal/api/validate.go/validate_test.go: POST /api/tasks/validate
- internal/api/server_test.go, storage/db_test.go: expanded test coverage
- scripts/reset-failed-tasks, reset-running-tasks
- web/app.js, index.html, style.css: frontend improvements
- web/test/: active-tasks-tab, delete-button, filter-tabs, sort-tasks tests

Manually applied from server.go diff (skipping Claude→Agent rename):
- taskLogStore field + validateCmdPath field
- DELETE /api/tasks/{id} route + handleDeleteTask
- GET /api/tasks/{id}/logs/stream route
- POST /api/tasks/{id}/resume route + handleResumeTimedOutTask
- handleCancelTask: allow cancelling PENDING/QUEUED tasks directly

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

1 files changed, 70 insertions, 33 deletions

diff --git a/web/app.js b/web/app.js
index ce1394d..97721d3 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1,5 +1,5 @@
-const BASE_PATH = document.querySelector('meta[name="base-path"]')?.content ?? '';
-const API_BASE = window.location.origin + BASE_PATH;
+const BASE_PATH = (typeof document !== 'undefined') ? document.querySelector('meta[name="base-path"]')?.content ?? '' : '';
+const API_BASE = (typeof window !== 'undefined') ? window.location.origin + BASE_PATH : '';
 
 // ── Fetch ─────────────────────────────────────────────────────────────────────
 
@@ -160,17 +160,56 @@ function createTaskCard(task) {
   return card;
 }
 
+// ── Sort ──────────────────────────────────────────────────────────────────────
+
+function sortTasksByDate(tasks) {
+  return [...tasks].sort((a, b) => {
+    if (!a.created_at && !b.created_at) return 0;
+    if (!a.created_at) return 1;
+    if (!b.created_at) return -1;
+    return new Date(a.created_at) - new Date(b.created_at);
+  });
+}
+
 // ── Filter ────────────────────────────────────────────────────────────────────
 
 const HIDE_STATES = new Set(['COMPLETED', 'FAILED']);
+const ACTIVE_STATES = new Set(['PENDING', 'QUEUED', 'RUNNING', 'READY', 'BLOCKED']);
+const DONE_STATES   = new Set(['COMPLETED', 'FAILED', 'TIMED_OUT', 'CANCELLED', 'BUDGET_EXCEEDED']);
 
-let showHiddenFold = false;
+// filterActiveTasks uses its own set (excludes PENDING — tasks "in-flight" only)
+const _PANEL_ACTIVE_STATES = new Set(['RUNNING', 'READY', 'QUEUED', 'BLOCKED']);
 
-function filterTasks(tasks, hideCompletedFailed = false) {
+export function filterTasks(tasks, hideCompletedFailed = false) {
   if (!hideCompletedFailed) return tasks;
   return tasks.filter(t => !HIDE_STATES.has(t.state));
 }
 
+export function filterActiveTasks(tasks) {
+  return tasks.filter(t => _PANEL_ACTIVE_STATES.has(t.state));
+}
+
+export function filterTasksByTab(tasks, tab) {
+  if (tab === 'active') return tasks.filter(t => ACTIVE_STATES.has(t.state));
+  if (tab === 'done')   return tasks.filter(t => DONE_STATES.has(t.state));
+  return tasks;
+}
+
+export function getTaskFilterTab() {
+  return localStorage.getItem('taskFilterTab') ?? 'active';
+}
+
+export function setTaskFilterTab(tab) {
+  localStorage.setItem('taskFilterTab', tab);
+}
+
+export function updateFilterTabs() {
+  const current = getTaskFilterTab();
+  document.querySelectorAll('.filter-tab[data-filter]').forEach(el => {
+    el.classList.toggle('active', el.dataset.filter === current);
+  });
+}
+
 function getHideCompletedFailed() {
   const stored = localStorage.getItem('hideCompletedFailed');
   return stored === null ? true : stored === 'true';
@@ -196,36 +235,30 @@ function renderTaskList(tasks) {
     return;
   }
 
-  const hide = getHideCompletedFailed();
-  const visible = filterTasks(tasks, hide);
-  const hiddenCount = tasks.length - visible.length;
+  const visible = sortTasksByDate(filterTasksByTab(tasks, getTaskFilterTab()));
 
   // Replace contents with task cards
   container.innerHTML = '';
   for (const task of visible) {
     container.appendChild(createTaskCard(task));
   }
+}
 
-  if (hiddenCount > 0) {
-    const info = document.createElement('button');
-    info.className = 'hidden-tasks-info';
-    const arrow = showHiddenFold ? '▼' : '▶';
-    info.textContent = `${arrow} ${hiddenCount} hidden task${hiddenCount === 1 ? '' : 's'}`;
-    info.addEventListener('click', () => {
-      showHiddenFold = !showHiddenFold;
-      renderTaskList(tasks);
-    });
-    container.appendChild(info);
-
-    if (showHiddenFold) {
-      const fold = document.createElement('div');
-      fold.className = 'hidden-tasks-fold';
-      const hiddenTasks = tasks.filter(t => HIDE_STATES.has(t.state));
-      for (const task of hiddenTasks) {
-        fold.appendChild(createTaskCard(task));
-      }
-      container.appendChild(fold);
-    }
+function renderActiveTaskList(tasks) {
+  const container = document.querySelector('.active-task-list');
+  if (!container) return;
+  if (!tasks || tasks.length === 0) {
+    container.innerHTML = '<div id="loading">No active tasks.</div>';
+    return;
+  }
+  const active = sortTasksByDate(filterActiveTasks(tasks));
+  container.innerHTML = '';
+  if (active.length === 0) {
+    container.innerHTML = '<div id="loading">No active tasks.</div>';
+    return;
+  }
+  for (const task of active) {
+    container.appendChild(createTaskCard(task));
   }
 }
 
@@ -762,6 +795,7 @@ async function poll() {
   try {
     const tasks = await fetchTasks();
     renderTaskList(tasks);
+    renderActiveTaskList(tasks);
   } catch {
     document.querySelector('.task-list').innerHTML =
       '<div id="loading">Could not reach server.</div>';
@@ -1539,12 +1573,15 @@ function switchTab(name) {
 
 // ── Boot ──────────────────────────────────────────────────────────────────────
 
-document.addEventListener('DOMContentLoaded', () => {
-  updateToggleButton();
-  document.getElementById('btn-toggle-completed').addEventListener('click', async () => {
-    setHideCompletedFailed(!getHideCompletedFailed());
-    updateToggleButton();
-    await poll();
+if (typeof document !== 'undefined') document.addEventListener('DOMContentLoaded', () => {
+  updateFilterTabs();
+
+  document.querySelectorAll(".filter-tab[data-filter]").forEach(btn => {
+    btn.addEventListener("click", () => {
+      setTaskFilterTab(btn.dataset.filter);
+      updateFilterTabs();
+      poll();
+    });
   });
 
   document.getElementById('btn-start-next').addEventListener('click', function() {