[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/lib/inbox.test.ts

@@ -611,7 +611,9 @@ describe("inbox helpers", () => {
     expect(
       buildInboxKeyboardNavEntries(groupedSections, new Set(), new Set()).map((entry) => entry.type === "top"
         ? entry.itemKey
-        : entry.issueId),
+        : entry.type === "child"
+          ? entry.issueId
+          : entry.groupKey),
     ).toEqual([
       `workspace:default:${getInboxWorkItemKey({ kind: "issue", timestamp: 2, issue: parentIssue })}`,
       childIssue.id,
@@ -620,12 +622,55 @@ describe("inbox helpers", () => {
     expect(
       buildInboxKeyboardNavEntries(groupedSections, new Set(), new Set([parentIssue.id])).map((entry) => entry.type === "top"
         ? entry.itemKey
-        : entry.issueId),
+        : entry.type === "child"
+          ? entry.issueId
+          : entry.groupKey),
     ).toEqual([
       `workspace:default:${getInboxWorkItemKey({ kind: "issue", timestamp: 2, issue: parentIssue })}`,
     ]);
   });
 
+  it("emits a group nav entry for labeled groups and omits children when the group is collapsed", () => {
+    const visibleIssue = makeIssue("visible", true);
+    const hiddenIssue = makeIssue("hidden", true);
+    const groupedSections = [
+      {
+        key: "priority:high",
+        label: "High priority",
+        displayItems: [{ kind: "issue", timestamp: 3, issue: visibleIssue } satisfies InboxWorkItem],
+        childrenByIssueId: new Map(),
+      },
+      {
+        key: "priority:medium",
+        label: "Medium priority",
+        displayItems: [{ kind: "issue", timestamp: 2, issue: hiddenIssue } satisfies InboxWorkItem],
+        childrenByIssueId: new Map(),
+      },
+    ];
+
+    const expanded = buildInboxKeyboardNavEntries(groupedSections, new Set(), new Set());
+    expect(expanded.map((entry) => entry.type)).toEqual(["group", "top", "group", "top"]);
+    expect(expanded[0]).toEqual({
+      type: "group",
+      groupKey: "priority:high",
+      label: "High priority",
+      collapsed: false,
+    });
+
+    const collapsed = buildInboxKeyboardNavEntries(
+      groupedSections,
+      new Set(["priority:medium"]),
+      new Set(),
+    );
+    expect(collapsed.map((entry) => entry.type)).toEqual(["group", "top", "group"]);
+    expect(collapsed[2]).toEqual({
+      type: "group",
+      groupKey: "priority:medium",
+      label: "Medium priority",
+      collapsed: true,
+    });
+  });
+
   it("sorts self-touched issues without external comments by updatedAt", () => {
     const recentSelfTouched = makeIssue("recent", false);
     recentSelfTouched.lastExternalCommentAt = null as unknown as Date;