Show blocker links in the task chat (#11456)

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(ASD-STE100): short sentences, one instruction per sentence, simple
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## Thinking Path

> - Paperclip helps operators supervise agent work through tasks and
task threads.
> - The redesigned task thread shows the current work and its state.
> - A blocked task did not show the dependency that prevented progress.
> - Operators had to leave the thread to find the direct and final
blockers.
> - This pull request adds compact blocker links at the top and bottom
of the task thread.
> - The benefit is that operators can identify and open the relevant
tasks without adding a large notice to the thread.

## Linked Issues or Issue Description

**What existing behavior does this improve?**

The redesigned task thread did not show which task directly blocked the
current task or which task ultimately blocked its dependency chain.

**Subsystem affected**

`server/`, `packages/shared/`, and `ui/` task-blocker presentation.

**Current behavior**

A blocked task can open in the redesigned thread without a visible
dependency link at the top or bottom of the conversation.

**Proposed behavior**

Show one compact amber row for the direct blocker. Show a second row for
the selected final blocker when one exists. Render the rows at both ends
of the thread.

**Reason and benefit**

Operators can see the reason for the blocked state and open the relevant
task from the conversation. The compact rows preserve thread density.

**Breaking changes**

None. The new blocker-attention fields are optional. Existing clients
remain compatible.

## What Changed

- Added a compact task-chat component for direct and selected final
blocker links.
- Added the blocker rows to the top and bottom of populated and empty
task threads.
- Added link-ready blocker-attention details so an intermediate selected
task stays on its correct direct chain.
- Included blocker-link changes in the thread content key so pinned
threads follow a newly added bottom row.
- Added component, scrolling, server contract, and Storybook coverage
for the new states.

## Verification

- `pnpm exec vitest run ui/src/components/TaskChatThread.test.tsx
server/src/__tests__/issue-blocker-attention.test.ts` (38 tests passed)
- `pnpm --filter @paperclipai/shared typecheck`
- `pnpm --filter @paperclipai/server typecheck`
- `pnpm --filter @paperclipai/ui typecheck`
- `pnpm check:token-gates`

## Risks

- Low risk. The rows only render while the task status is `blocked` and
an unresolved blocker is available.
- Long titles are truncated to keep each blocker on one line. The full
task label remains available in the link title.
- Older server payloads keep the original leaf-selection behavior
because the new sampled details are optional.

> 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 with GPT-5. The run used tool-enabled reasoning and code
execution. The context-window size was not exposed to the run.

## 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 searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

Author: cryppadotta

packages/shared/src/index.ts

@@ -951,6 +951,7 @@ export type {
   IssueSubtreeDiagnosticEdge,
   IssueSubtreeDiagnosticsResponse,
   IssueBlockerAttention,
+  IssueBlockerAttentionIssueSummary,
   IssueBlockerAttentionReason,
   IssueBlockerAttentionState,
   IssueReviewAttention,

packages/shared/src/types/index.ts

@@ -604,6 +604,7 @@ export type {
   IssueSubtreeDiagnosticEdge,
   IssueSubtreeDiagnosticsResponse,
   IssueBlockerAttention,
+  IssueBlockerAttentionIssueSummary,
   IssueBlockerAttentionReason,
   IssueBlockerAttentionState,
   IssueReviewAttention,

packages/shared/src/types/issue.ts

@@ -396,6 +396,12 @@ export type IssueBlockerAttentionReason =
   | "attention_required"
   | null;
 
+export interface IssueBlockerAttentionIssueSummary {
+  id: string;
+  identifier: string | null;
+  title: string;
+}
+
 export interface IssueBlockerAttention {
   state: IssueBlockerAttentionState;
   reason: IssueBlockerAttentionReason;
@@ -408,8 +414,12 @@ export interface IssueBlockerAttention {
   sampleStalledBlockerIdentifier: string | null;
   /** True when a blocker or one of its open descendants is actively progressing. */
   blockingTreeLive?: boolean;
-  /** The sampled leaf blocker that requires action, rather than the blocked root. */
+  /** The direct blocker whose chain contains the sampled terminal blocker. */
+  directBlockerIssueId?: string | null;
+  /** The sampled blocker that requires action, rather than the blocked root. */
   terminalBlockerIssueId?: string | null;
+  /** Link-ready details for the sampled blocker, including non-terminal intermediate nodes. */
+  terminalBlocker?: IssueBlockerAttentionIssueSummary | null;
 }
 
 export type IssueReviewAttentionState = "none" | "covered" | "stalled";

server/src/__tests__/issue-blocker-attention.test.ts

@@ -447,6 +447,47 @@ describeEmbeddedPostgres("issue blocker attention", () => {
     });
   });
 
+  it("returns the direct path and link details when an intermediate blocker is selected", async () => {
+    const { companyId, agentId } = await createCompany("PBI");
+    const rootId = await insertIssue({ companyId, identifier: "PBI-1", title: "Root", status: "blocked" });
+    const directId = await insertIssue({
+      companyId,
+      identifier: "PBI-2",
+      title: "Direct blocker",
+      status: "blocked",
+    });
+    const intermediateId = await insertIssue({
+      companyId,
+      identifier: "PBI-3",
+      title: "Stalled intermediate review",
+      status: "in_review",
+      assigneeAgentId: agentId,
+    });
+    const leafId = await insertIssue({
+      companyId,
+      identifier: "PBI-4",
+      title: "Downstream leaf",
+      status: "todo",
+      assigneeAgentId: agentId,
+    });
+    await block({ companyId, blockerIssueId: directId, blockedIssueId: rootId });
+    await block({ companyId, blockerIssueId: intermediateId, blockedIssueId: directId });
+    await block({ companyId, blockerIssueId: leafId, blockedIssueId: intermediateId });
+
+    const root = (await svc.list(companyId, { status: "blocked" })).find((issue) => issue.id === rootId);
+
+    expect(root?.blockerAttention).toMatchObject({
+      state: "stalled",
+      directBlockerIssueId: directId,
+      terminalBlockerIssueId: intermediateId,
+      terminalBlocker: {
+        id: intermediateId,
+        identifier: "PBI-3",
+        title: "Stalled intermediate review",
+      },
+    });
+  });
+
   it("prefers needs_attention over stalled when the chain also has a hard attention case", async () => {
     const { companyId, agentId } = await createCompany("PBQ");
     const parentId = await insertIssue({ companyId, identifier: "PBQ-1", title: "Parent", status: "blocked" });

server/src/services/issues.ts

@@ -2094,7 +2094,9 @@ function createIssueBlockerAttention(input: Partial<IssueBlockerAttention> = {})
     sampleBlockerIdentifier: input.sampleBlockerIdentifier ?? null,
     sampleStalledBlockerIdentifier: input.sampleStalledBlockerIdentifier ?? null,
     blockingTreeLive: input.blockingTreeLive ?? false,
+    directBlockerIssueId: input.directBlockerIssueId ?? null,
     terminalBlockerIssueId: input.terminalBlockerIssueId ?? null,
+    terminalBlocker: input.terminalBlocker ?? null,
   };
 }
 
@@ -2758,6 +2760,11 @@ async function listIssueBlockerAttentionMap(
     const sampledTerminalIdentifier = sampleEntry?.result.stalled
       ? sampleEntry.result.sampleStalledBlockerIdentifier ?? sampleEntry.result.sampleBlockerIdentifier
       : sampleEntry?.result.sampleBlockerIdentifier ?? blockerSampleIdentifier(sampleNode);
+    const terminalBlockerIssueId =
+      sampleEntry?.result.terminalBlockerIssueId ?? issueIdForSample(sampledTerminalIdentifier);
+    const terminalBlockerNode = terminalBlockerIssueId
+      ? nodesById.get(terminalBlockerIssueId) ?? null
+      : null;
 
     let state: IssueBlockerAttention["state"];
     let reason: IssueBlockerAttention["reason"];
@@ -2788,8 +2795,15 @@ async function listIssueBlockerAttentionMap(
       sampleStalledBlockerIdentifier:
         stalledEntry?.result.sampleStalledBlockerIdentifier ?? sampleStalledFromChain ?? null,
       blockingTreeLive: topLevelEdges.some((edge) => pathHasLiveWork(edge.blockerIssueId, new Set([root.id]))),
-      terminalBlockerIssueId:
-        sampleEntry?.result.terminalBlockerIssueId ?? issueIdForSample(sampledTerminalIdentifier),
+      directBlockerIssueId: sampleEntry?.edge.blockerIssueId ?? null,
+      terminalBlockerIssueId,
+      terminalBlocker: terminalBlockerNode
+        ? {
+            id: terminalBlockerNode.id,
+            identifier: terminalBlockerNode.identifier,
+            title: terminalBlockerNode.title,
+          }
+        : null,
     }));
   }