[codex] Add blocked inbox attention view (#5603)

## Thinking Path

> - Paperclip orchestrates AI agents for zero-human companies through
company-scoped issues, comments, approvals, and execution workspaces.
> - Operators need the Inbox to show not only active work, but also
blocked work that may need human or agent attention.
> - The existing inbox experience did not have a dedicated blocked-work
surface, so blocked tasks were harder to triage and resume deliberately.
> - Backend consumers also needed a compact attention signal that
distinguishes actionable blockers from covered or waiting blocker
states.
> - This pull request adds a Blocked Inbox tab backed by issue
blocker-attention metadata, shared validators, and UI helpers.
> - The benefit is a clearer triage path for stalled or blocked
Paperclip work without exposing external wait internals in the
operator-facing UI.

## What Changed

- Added shared issue blocker-attention types, validators, and exports
for the API/UI contract.
- Added backend blocker-attention computation and issue route support
for blocked inbox data.
- Added the Blocked Inbox tab, blocked reason chips, filtering/search
UI, responsive layouts, and Storybook stories.
- Updated inbox helpers and page behavior so toolbar controls only
appear where they apply.
- Added coverage for shared validators, server blocker-attention
behavior, blocked inbox UI helpers/components, and the Inbox page.
- Added a screenshot helper script for the blocked inbox Storybook
stories.
- Addressed Greptile feedback by making urgency sorting deterministic
for null stop times, avoiding full blocked-inbox list enrichment for
counts, and hardening the screenshot helper.

## Verification

- Rebased the branch cleanly onto `public-gh/master`.
- Confirmed the diff does not include `pnpm-lock.yaml`.
- Confirmed the diff does not include database migration files.
- Ran `pnpm exec vitest run packages/shared/src/validators/issue.test.ts
server/src/__tests__/issue-blocker-attention.test.ts
ui/src/components/BlockedInboxView.test.tsx
ui/src/components/BlockedReasonChip.test.tsx
ui/src/lib/blockedInbox.test.ts ui/src/lib/inbox.test.ts
ui/src/pages/Inbox.test.tsx`.
- Ran `pnpm --filter @paperclipai/shared typecheck && pnpm --filter
@paperclipai/server typecheck && pnpm --filter @paperclipai/ui
typecheck`.
- Checked `ROADMAP.md`; this is scoped inbox/operator triage work and
does not duplicate a listed roadmap feature.
- Greptile Review is green on the latest head and all four Greptile
review threads are resolved.
- GitHub PR checks are green on the latest head: policy, security/snyk,
e2e, verify, Canary Dry Run, Greptile Review, and serialized server
suites 1/4 through 4/4.

## Risks

- Medium review surface because this touches the shared issue contract,
server issue services, and the Inbox UI together.
- Blocker-attention classification may need product tuning after
operators use it on real blocked queues.
- UI screenshots were not attached in this PR-opening pass; the branch
includes `scripts/screenshot-blocked-inbox.mjs` and Storybook stories
for visual capture.

> 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 with shell, git, GitHub CLI,
GitHub connector, and Paperclip API tool use. Reasoning mode: medium.
Context window: not exposed by the runtime.

## 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

---------

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

ui/src/api/issues.ts

@@ -37,6 +37,7 @@ export const issuesApi = {
   list: (
     companyId: string,
     filters?: {
+      attention?: "blocked";
       status?: string;
       projectId?: string;
       parentId?: string;
@@ -55,12 +56,14 @@ export const issuesApi = {
       descendantOf?: string;
       includeRoutineExecutions?: boolean;
       includeBlockedBy?: boolean;
+      includeBlockedInboxAttention?: boolean;
       q?: string;
       limit?: number;
       offset?: number;
     },
   ) => {
     const params = new URLSearchParams();
+    if (filters?.attention) params.set("attention", filters.attention);
     if (filters?.status) params.set("status", filters.status);
     if (filters?.projectId) params.set("projectId", filters.projectId);
     if (filters?.parentId) params.set("parentId", filters.parentId);
@@ -79,12 +82,35 @@ export const issuesApi = {
     if (filters?.descendantOf) params.set("descendantOf", filters.descendantOf);
     if (filters?.includeRoutineExecutions) params.set("includeRoutineExecutions", "true");
     if (filters?.includeBlockedBy) params.set("includeBlockedBy", "true");
+    if (filters?.includeBlockedInboxAttention) params.set("includeBlockedInboxAttention", "true");
     if (filters?.q) params.set("q", filters.q);
     if (filters?.limit) params.set("limit", String(filters.limit));
     if (filters?.offset !== undefined) params.set("offset", String(filters.offset));
     const qs = params.toString();
     return api.get<Issue[]>(`/companies/${companyId}/issues${qs ? `?${qs}` : ""}`);
   },
+  count: (
+    companyId: string,
+    filters: {
+      attention: "blocked";
+      status?: string;
+      assigneeAgentId?: string;
+      assigneeUserId?: string;
+      projectId?: string;
+      labelId?: string;
+      q?: string;
+    },
+  ) => {
+    const params = new URLSearchParams();
+    params.set("attention", filters.attention);
+    if (filters.status) params.set("status", filters.status);
+    if (filters.assigneeAgentId) params.set("assigneeAgentId", filters.assigneeAgentId);
+    if (filters.assigneeUserId) params.set("assigneeUserId", filters.assigneeUserId);
+    if (filters.projectId) params.set("projectId", filters.projectId);
+    if (filters.labelId) params.set("labelId", filters.labelId);
+    if (filters.q) params.set("q", filters.q);
+    return api.get<{ count: number }>(`/companies/${companyId}/issues/count?${params.toString()}`);
+  },
   listLabels: (companyId: string) => api.get<IssueLabel[]>(`/companies/${companyId}/labels`),
   createLabel: (companyId: string, data: { name: string; color: string }) =>
     api.post<IssueLabel>(`/companies/${companyId}/labels`, data),