[codex] Split backend control-plane QoL slice (#4700)

## Thinking Path

> - Paperclip is the control plane for autonomous AI companies, so
backend task ownership, recovery, review visibility, and company-scoped
limits need to stay enforceable without UI-only coupling.
> - Closed PR #4692 bundled those backend changes with UI workflow,
docs, skills, workflow, and lockfile churn.
> - PAP-2694 asks for a clean backend/control-plane slice from that
closed branch.
> - This branch starts from current `master` and mines only the `cli`,
`packages/db`, `packages/shared`, and `server` contracts/tests needed
for the backend behavior.
> - It explicitly excludes UI workflow/performance work,
`.github/workflows/pr.yml`, `pnpm-lock.yaml`, docs, skills,
package-script, adapter UI build-config, and perf fixture script
changes; the only UI files are fixture/test updates required by the
tightened shared `Company` contract.
> - The benefit is a smaller reviewable PR that preserves the
control-plane fixes while staying under Greptile s 100-file review
limit.

## What Changed

- Added company-scoped attachment-size limits through DB
schema/migrations, shared company portability contracts, CLI
import/export coverage, and server attachment upload enforcement.
- Added productivity review service/API behavior for no-comment streak,
long-active, and high-churn review issues, including request-depth
clamping and issue summary exposure.
- Hardened issue ownership and recovery/control-plane paths: peer-agent
mutation denial, issue tree pause/resume behavior, stranded recovery
origins, and related activity/test coverage.
- Preserved related backend contract updates for routine timestamp
variables and managed agent instruction bundles because they live in
shared/server contracts from the source branch.
- Addressed Greptile feedback by making `Company.attachmentMaxBytes`
non-optional, simplifying review request-depth clamping, fixing the
migration final newline, and enforcing the process-level attachment cap
as the final ceiling for uploads.
- Added minimal company fixtures needed for repo-wide typecheck/build
and kept the PR to 66 changed files with forbidden/non-slice paths
excluded.

## Verification

- `pnpm install --frozen-lockfile`
- `git diff --check origin/master..HEAD`
- `git diff --name-only origin/master..HEAD | wc -l` -> 66 files
- `git diff --name-only origin/master..HEAD -- .github/workflows/pr.yml
pnpm-lock.yaml package.json doc skills .agents scripts
packages/adapters` -> no output
- `pnpm exec vitest run --config vitest.config.ts
packages/shared/src/validators/issue.test.ts
packages/shared/src/routine-variables.test.ts
packages/shared/src/adapter-types.test.ts
cli/src/__tests__/company-import-export-e2e.test.ts
cli/src/__tests__/company.test.ts
server/src/__tests__/productivity-review-service.test.ts
server/src/__tests__/issue-tree-control-service.test.ts
server/src/__tests__/issue-tree-control-routes.test.ts
server/src/__tests__/issue-agent-mutation-ownership-routes.test.ts
server/src/__tests__/issue-attachment-routes.test.ts
server/src/__tests__/heartbeat-process-recovery.test.ts
server/src/__tests__/issues-service.test.ts` -> 12 files, 147 tests
passed
- `pnpm exec vitest run --config vitest.config.ts
cli/src/__tests__/company-delete.test.ts
cli/src/__tests__/company-import-export-e2e.test.ts
server/src/__tests__/productivity-review-service.test.ts` -> 3 files, 18
tests passed
- `pnpm exec vitest run --config vitest.config.ts
server/src/__tests__/issue-attachment-routes.test.ts` -> 1 file, 6 tests
passed
- `pnpm --filter @paperclipai/db typecheck && pnpm --filter
@paperclipai/shared typecheck && pnpm --filter @paperclipai/server
typecheck && pnpm --filter paperclipai typecheck`
- `pnpm --filter @paperclipai/server typecheck`
- `pnpm --filter @paperclipai/ui typecheck && pnpm --filter
@paperclipai/ui build`

## Risks

- Includes migrations `0073_shiny_salo.sql` and
`0074_striped_genesis.sql`; merge ordering matters if another PR adds
migrations first.
- This is intentionally backend-only apart from fixture/test updates
forced by shared type correctness; UI affordances from PR #4692 are not
present here and should land in separate UI slices.
- The worktree install emitted plugin SDK bin-link warnings for unbuilt
plugin packages, but the targeted tests and package typechecks completed
successfully.

> 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 coding agent, tool-enabled terminal/GitHub
workflow. Exact runtime context window was not exposed by the harness.

## 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
- [x] 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>

server/src/__tests__/heartbeat-dependency-scheduling.test.ts

@@ -672,7 +672,8 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
     const companyId = randomUUID();
     const agentId = randomUUID();
     const rootIssueId = randomUUID();
-    const childIssueId = randomUUID();
+    const issueChain = Array.from({ length: 17 }, () => randomUUID());
+    const deepDescendantIssueId = issueChain.at(-1)!;
 
     await db.insert(companies).values({
       id: companyId,
@@ -705,15 +706,15 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
         priority: "medium",
         assigneeAgentId: agentId,
       },
-      {
-        id: childIssueId,
+      ...issueChain.map((issueId, index) => ({
+        id: issueId,
         companyId,
-        parentId: rootIssueId,
-        title: "Paused child",
+        parentId: index === 0 ? rootIssueId : issueChain[index - 1],
+        title: `Paused desc ${index + 1}`,
         status: "todo",
         priority: "medium",
         assigneeAgentId: agentId,
-      },
+      })),
     ]);
     const [hold] = await db
       .insert(issueTreeHolds)
@@ -731,8 +732,8 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
       source: "automation",
       triggerDetail: "system",
       reason: "issue_blockers_resolved",
-      payload: { issueId: childIssueId },
-      contextSnapshot: { issueId: childIssueId, wakeReason: "issue_blockers_resolved" },
+      payload: { issueId: deepDescendantIssueId },
+      contextSnapshot: { issueId: deepDescendantIssueId, wakeReason: "issue_blockers_resolved" },
     });
 
     expect(blockedWake).toBeNull();
@@ -742,7 +743,7 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
         reason: agentWakeupRequests.reason,
       })
       .from(agentWakeupRequests)
-      .where(sql`${agentWakeupRequests.payload} ->> 'issueId' = ${childIssueId}`)
+      .where(sql`${agentWakeupRequests.payload} ->> 'issueId' = ${deepDescendantIssueId}`)
       .then((rows) => rows[0] ?? null);
     expect(skippedWake).toMatchObject({ status: "skipped", reason: "issue_tree_hold_active" });
 
@@ -750,7 +751,7 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
     await db.insert(issueComments).values({
       id: childCommentId,
       companyId,
-      issueId: childIssueId,
+      issueId: deepDescendantIssueId,
       authorUserId: "board-user",
       body: "Please respond while this hold is active.",
     });
@@ -759,7 +760,7 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
       source: "on_demand",
       triggerDetail: "manual",
       reason: "issue_commented",
-      payload: { issueId: childIssueId, commentId: childCommentId },
+      payload: { issueId: deepDescendantIssueId, commentId: childCommentId },
       requestedByActorType: "agent",
       requestedByActorId: agentId,
     });
@@ -769,11 +770,11 @@ describeEmbeddedPostgres("heartbeat dependency-aware queued run selection", () =
       source: "automation",
       triggerDetail: "system",
       reason: "issue_commented",
-      payload: { issueId: childIssueId, commentId: childCommentId },
+      payload: { issueId: deepDescendantIssueId, commentId: childCommentId },
       requestedByActorType: "user",
       requestedByActorId: "board-user",
       contextSnapshot: {
-        issueId: childIssueId,
+        issueId: deepDescendantIssueId,
         commentId: childCommentId,
         wakeCommentId: childCommentId,
         wakeReason: "issue_commented",