[codex] Polish issue board workflows (#4224)

## Thinking Path

> - Paperclip orchestrates AI agents for zero-human companies
> - Human operators supervise that work through issue lists, issue
detail, comments, inbox groups, markdown references, and
profile/activity surfaces
> - The branch had many small UI fixes that improve the operator loop
but do not need to ship with backend runtime migrations
> - These changes belong together as board workflow polish because they
affect scanning, navigation, issue context, comment state, and markdown
clarity
> - This pull request groups the UI-only slice so it can merge
independently from runtime/backend changes
> - The benefit is a clearer board experience with better issue context,
steadier optimistic updates, and more predictable keyboard navigation

## What Changed

- Improves issue properties, sub-issue actions, blocker chips, and issue
list/detail refresh behavior.
- Adds blocker context above the issue composer and stabilizes
queued/interrupted comment UI state.
- Improves markdown issue/GitHub link rendering and opens external
markdown links in a new tab.
- Adds inbox group keyboard navigation and fold/unfold support.
- Polishes activity/avatar/profile/settings/workspace presentation
details.

## Verification

- `pnpm exec vitest run ui/src/components/IssueProperties.test.tsx
ui/src/components/IssueChatThread.test.tsx
ui/src/components/MarkdownBody.test.tsx ui/src/lib/inbox.test.ts
ui/src/lib/optimistic-issue-comments.test.ts`

## Risks

- Low to medium risk: changes are UI-focused but cover high-traffic
issue and inbox surfaces.
- This branch intentionally does not include the backend runtime changes
from the companion PR; where UI calls newer API filters, unsupported
servers should continue to fail visibly through existing API error
handling.
- Visual screenshots were not captured in this heartbeat; targeted
component/helper tests cover the changed behavior.

> For core feature work, check [`ROADMAP.md`](ROADMAP.md) first and
discuss it in `#dev` before opening the PR. Feature PRs that overlap
with planned core work may need to be redirected — check the roadmap
first. See `CONTRIBUTING.md`.

## Model Used

- OpenAI Codex, GPT-5-based coding agent runtime, shell/git tool use
enabled. Exact hosted model build and context window are not exposed in
this Paperclip heartbeat environment.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [ ] If this change affects the UI, I have included before/after
screenshots
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

ui/src/components/IssueChatThread.test.tsx

@@ -5,6 +5,7 @@ import type { ReactNode } from "react";
 import { createRoot } from "react-dom/client";
 import { MemoryRouter } from "react-router-dom";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import type { Agent } from "@paperclipai/shared";
 import {
   IssueChatThread,
   canStopIssueChatRun,
@@ -113,6 +114,24 @@ vi.mock("./StatusBadge", () => ({
   StatusBadge: ({ status }: { status: string }) => <span>{status}</span>,
 }));
 
+vi.mock("./IssueLinkQuicklook", () => ({
+  IssueLinkQuicklook: ({
+    children,
+    to,
+    issuePathId,
+    className,
+  }: {
+    children: ReactNode;
+    to: string;
+    issuePathId: string;
+    className?: string;
+  }) => (
+    <a href={to} data-issue-path-id={issuePathId} className={className}>
+      {children}
+    </a>
+  ),
+}));
+
 vi.mock("../hooks/usePaperclipIssueRuntime", () => ({
   usePaperclipIssueRuntime: () => ({}),
 }));
@@ -171,6 +190,83 @@ describe("IssueChatThread", () => {
     });
   });
 
+  it("shows unresolved blocker context above the composer", () => {
+    const root = createRoot(container);
+
+    act(() => {
+      root.render(
+        <MemoryRouter>
+          <IssueChatThread
+            comments={[]}
+            linkedRuns={[]}
+            timelineEvents={[]}
+            liveRuns={[]}
+            issueStatus="todo"
+            blockedBy={[
+              {
+                id: "blocker-1",
+                identifier: "PAP-1723",
+                title: "QA the install flow",
+                status: "blocked",
+                priority: "medium",
+                assigneeAgentId: "agent-1",
+                assigneeUserId: null,
+              },
+            ]}
+            onAdd={async () => {}}
+            enableLiveTranscriptPolling={false}
+          />
+        </MemoryRouter>,
+      );
+    });
+
+    expect(container.textContent).toContain("Work on this issue is blocked by the linked issue");
+    expect(container.textContent).toContain("Comments still wake the assignee for questions or triage");
+    expect(container.textContent).toContain("PAP-1723");
+    expect(container.textContent).toContain("QA the install flow");
+    expect(container.querySelector('[data-issue-path-id="PAP-1723"]')).not.toBeNull();
+
+    act(() => {
+      root.unmount();
+    });
+  });
+
+  it("shows paused assigned agent context above the composer", () => {
+    const root = createRoot(container);
+    const pausedAgent = {
+      id: "agent-1",
+      companyId: "company-1",
+      name: "CodexCoder",
+      status: "paused",
+      pauseReason: "manual",
+    } as Agent;
+
+    act(() => {
+      root.render(
+        <MemoryRouter>
+          <IssueChatThread
+            comments={[]}
+            linkedRuns={[]}
+            timelineEvents={[]}
+            liveRuns={[]}
+            agentMap={new Map([["agent-1", pausedAgent]])}
+            currentAssigneeValue="agent:agent-1"
+            onAdd={async () => {}}
+            enableLiveTranscriptPolling={false}
+          />
+        </MemoryRouter>,
+      );
+    });
+
+    expect(container.textContent).toContain("CodexCoder is paused");
+    expect(container.textContent).toContain("New runs will not start until the agent is resumed");
+    expect(container.textContent).toContain("It was paused manually");
+
+    act(() => {
+      root.unmount();
+    });
+  });
+
   it("supports the embedded read-only variant without the jump control", () => {
     const root = createRoot(container);