Agent org structure and roster (WI-045)

[nateshpp]

What this PR does

Adds the canonical description of the agent org: who is in the crew, what each agent is for, and how each is configured on a model, runner, schedule, and trigger. This is the documentation artifact; the machinery it describes already exists (roles registry, capability profiles, and the WI-032 trigger and schedule layer). Closes WI-045.

Stacked on #125 (base is feature/configurable-trigger-layer, since the docs describe that PR's code). Merge #125 first, then this rebases onto main.

• docs/adr/ADR-044-agent-org-structure.md: the structure decision. The agent org is the roles registry governed by two checkpoints; specialists are governed config-only crew roles, not a flat personality dump; every agent is configurable on model, runtime, schedule, and trigger from config; the crew stays lean with an envisioner and a market-researcher as the only planned additions.
• docs/agent-org.md: the canonical roster (canonical: agent-org). A crew table with per-agent model recommendations, the per-role config field reference, the steps to add or change an agent, and a pointer to the control panel as the operator surface for choosing each agent's model, schedule, and trigger.
• ARCHITECTURE.md and docs/README.md: link to the roster and the ADR.

Governance checklist

• npm run verify passes locally through every governance gate (markdown-governance links/ADR-numbers/canonical keys clean) and AgentProof (25/25). Stops only at check:frontend/npm test on missing dev deps (esbuild, js-yaml) that CI installs.
• No em dashes in any tracked file
• Prose states conclusions directly
• No AI co-author lines in commit messages
• Ratchet logic unchanged (n/a)
• No new AgentProof scenario (n/a)
• Config schema unchanged (n/a)
• Prompt unchanged (n/a)

Test evidence

$ node scripts/check-md-governance.mjs
PASS: root allow-list, protected files, links, ADR numbers, audits, and canonical keys all clean.

$ node scripts/check-architecture-drift.mjs
Architecture drift guard: every execution surface, script reference, and work-item state is accounted for.

$ node scripts/check-work-items.mjs
PASS: 44 work item(s) valid; maker and checker stay distinct.