feat(tasks): phase 6 — live TaskContextPanel (goal, plan, question, entities)

Replaces the chat right rail's ad-hoc Digest+Graph stack with a single
TaskContextPanel that renders the task's live working state, driven by the
always-on events stream (not the per-turn chat SSE) so it keeps updating
during server-side auto-continuation/resume:

- GoalHeader: goal + status pill (planning/executing/awaiting_input/done/
  failed), sourced from the sessions list.
- PlanProgress: ordered steps with live status icons + progress bar, hydrated
  via new GET /sessions/{id}/plan; clicking a step with a target opens its
  EntitySheet (no fake "jump to transcript" — bits-ui Collapsible content
  isn't force-mounted, so a DOM-scroll jump would silently no-op for
  collapsed tool groups).
- OperatorQuestion: the pinned structured question card (prompt/why/entity
  chips/option buttons/free-text), hydrated via new GET /sessions/{id}/
  questions; answering POSTs to the existing answer endpoint.
- SessionGraph upgraded to a live entity panel: entity.touched pulses the
  node (animated ring) and shows "Now touching <slug>"; health.changed shows
  a transient diff badge for touched entities.
- SessionDigest gains a success/failure/partial outcome banner and now also
  refetches when the task's status changes, not just on session switch.

Two bugs found and fixed while wiring this up:
- workspace.ts's status-refresh trigger only covered goal.set/task.status;
  question.raised/answered didn't refresh the sessions list, so GoalHeader's
  pill went stale after answering via the panel (resumeSession runs entirely
  server-side — no client 'done' event to piggyback a refresh on). Now every
  status-affecting event triggers the (debounced) refetch.
- Forgot to rebuild the nomos container after adding the /plan and
  /questions endpoints, so they silently fell through to the old default GET
  handler — caught via a live curl diff against the running container,
  not a code read.

Verified end-to-end against the live stack: goal/plan/question all update
without a reload as the agent works; answering a question via the panel
resumes the agent and the header pill correctly flips to Executing;
entity.touched pulses the live graph.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/src/lib/components/OperatorQuestion.svelte

@@ -0,0 +1,76 @@
+<script lang="ts">
+  import { openQuestion } from '$lib/stores/workspace'
+  import { currentSession } from '$lib/stores/chat'
+  import { answerQuestion as postAnswer } from '$lib/api'
+  import { Button } from '$lib/components/ui/button'
+  import { Textarea } from '$lib/components/ui/textarea'
+  import CircleHelpIcon from '@lucide/svelte/icons/circle-help'
+
+  let freeText = $state('')
+  let submitting = $state(false)
+
+  async function submit(answer: string) {
+    const sid = $currentSession
+    const q = $openQuestion
+    if (!sid || !q || !answer.trim() || submitting) return
+    submitting = true
+    const ok = await postAnswer(sid, q.id, answer.trim())
+    submitting = false
+    if (ok) freeText = ''
+    // No local optimistic clear: the question.answered event (which the POST
+    // triggers server-side) updates the store — this stays truthful if the
+    // POST reports ok but the event is somehow delayed.
+  }
+</script>
+
+{#if $openQuestion}
+  {@const q = $openQuestion}
+  <div class="flex shrink-0 flex-col gap-2 border-b bg-warning/5 px-3 py-2.5">
+    <div class="flex items-start gap-2">
+      <CircleHelpIcon class="mt-0.5 size-4 shrink-0 text-warning" />
+      <div class="min-w-0 flex-1">
+        <p class="text-sm font-medium leading-snug">{q.prompt}</p>
+        {#if q.context.why}
+          <p class="mt-0.5 text-xs text-muted-foreground">{q.context.why}</p>
+        {/if}
+      </div>
+    </div>
+
+    {#if q.context.entities?.length}
+      <div class="ml-6 flex flex-wrap gap-1">
+        {#each q.context.entities as slug}
+          <span class="rounded bg-muted px-1.5 py-0.5 font-mono text-[10px]">{slug}</span>
+        {/each}
+      </div>
+    {/if}
+
+    {#if q.context.options?.length}
+      <div class="ml-6 flex flex-wrap gap-1.5">
+        {#each q.context.options as opt}
+          <Button size="sm" variant="outline" class="h-7 px-2.5 text-xs" disabled={submitting} onclick={() => submit(opt)}>
+            {opt}
+          </Button>
+        {/each}
+      </div>
+    {/if}
+
+    <div class="ml-6 flex items-end gap-1.5">
+      <Textarea
+        bind:value={freeText}
+        placeholder="Or type an answer…"
+        rows={1}
+        class="max-h-24 min-h-0 resize-none text-xs"
+        disabled={submitting}
+        onkeydown={(e) => {
+          if (e.key === 'Enter' && !e.shiftKey) {
+            e.preventDefault()
+            submit(freeText)
+          }
+        }}
+      />
+      <Button size="sm" class="h-7 px-2.5 text-xs" disabled={!freeText.trim() || submitting} onclick={() => submit(freeText)}>
+        Send
+      </Button>
+    </div>
+  </div>
+{/if}