feat(app): the Campaign tab — the Work Column's full-ledger drill-down

[aarontrowbridge]

The slice

The campaign-digest widget (#690) is the home tile; the Campaign tab is its drill-down sibling — a Work Column tab rendering the FULL campaign ledger view for the active campaign: the objective, the complete verdict table (unit → status → evidence), the blocked queue with reasons, and the loop log — everything GET /amicode/campaigns and the per-campaign detail route (#662) already serve.

Acceptance criteria

• A Campaign tab in the Work Column's tab structure (explore the overlay's tab/navigation pattern — session.tsx and context/layout.tsx carry the campaign context today).
• Full-ledger rendering: objective, verdict table, blocked queue, loop log — empty-state everywhere appropriate (no campaign → the tab explains how one starts).
• Data from the existing campaign routes (feat(service): campaign routes — GET /amicode/campaigns + /amicode/campaign over the session ledgers (#658) #662) — no new server surface unless the detail route lacks a field the table needs (then extend the route + fixtures per the fix(amico-run): bundle-build CI gate + upgrade-path dist rebuild — no more stale verb router (#643) #647 golden discipline).
• The digest tile's click path deep-links into the tab (the tile already composes amico.prompt — the tab is the readable surface beside it).
• Escaping/empty-state/theme discipline per the feat(widget): campaign-digest built-in — the home-dashboard digest over the campaign routes (#678) #690 precedent; the app-bundle golden gate stays clean.

Pointers

• Server: packages/extension/src/amicode_service/campaign_ledger.ts (the data path), index.ts (the routes), widgets_src/campaign-digest.ts (the digest's rendering pattern).
• App: packages/app-bundle/overlay/packages/app/src/context/layout.tsx, pages/session.tsx (campaign context today); the Work Column's tab structure (explore).
• Discipline: PR → CI (7 checks) → merge; the app-bundle gate's golden contract re-records per the BUG: Vault knowledge-graph note click opens blank markdown #447/feat(widget): campaign-digest built-in — the home-dashboard digest over the campaign routes (#678) #690 precedent if the built-in set changes.