docs: add operator-seat orchestration guide

[cdonovan-abtex]

Hi — I adopted firstmate a while back and it's become the backbone of how I run a fleet of repos.
This doc is a small bit back.

Where I'm coming from, since it's the angle: I'm a Navy veteran and the GM of a manufacturing company — I own a P&L, and I also build the software the business runs on (CS/Math undergrad, MBA).
So I use firstmate from a seat that isn't the usual one: not an engineer managing parallel projects, but an operator commanding agents against systems where a mistake is a business event, not a failed test.

docs/operator-seat.md writes that seat up.
It builds on your design, not over it — the core (orchestrator conducts not codes, escalate only judgment, isolation, reliability-as-the-whole-game) is yours, and I think you nailed it.
The doc adds (1) the operator lens and why it raises the scrutiny bar, and (2) the CAPTAINS-INTENT pattern: a committed CAPTAINS-INTENT.md per repo — north star, a Toyota-style 5 Whys, boundaries, a tie-back test — that turns "use good judgment" into something testable, plus two security lessons that seat taught me the hard way (review must weigh repo visibility; security-clear ≠ intent-correct).

Aside: you and I seem to have derived a lot of the same principles independently — I was sold enough by your execution to adopt yours rather than keep building my own.
Hopefully a useful addition from the operator end.
Happy to revise to fit the project's voice.

What Changed

• Adds docs/operator-seat.md (+104 lines), a conceptual essay describing the "operator's seat" — intent-governed orchestration for someone accountable for business outcomes who also commands a crew of coding agents.
• Introduces the CAPTAINS-INTENT.md pattern (north star, Toyota-style 5 Whys, heart, boundaries, tie-back test) and the firstmate/helmsman duty split, with a runway-guard enforcement layer that hard-stops on drift.
• The doc is new and currently unlinked from README or any docs index; surfacing it is left as a maintainer decision.

Risk Assessment

✅ Low: The change adds a single standalone documentation file with no code, scripts, or shared-machinery impact, and it explicitly distinguishes aspirational concepts from what is built today.

Testing

There is no automated test surface for this documentation-only change, so I validated it the way a reviewer would: I audited the prose against every element of the author's intent (all present and consistent), confirmed the file is valid GitHub-flavored markdown by rendering it with pandoc (no warnings), and captured a full-page screenshot of the rendered document to show it displays correctly — title, all five sections, lists, inline code, and emphasis all render as intended. Worktree left clean.

• Evidence: Rendered operator-seat.md (full-page screenshot) (local file: /var/folders/l8/htqy6t0j6hd9y084y1jqmqbr0000gn/T/no-mistakes-evidence/01KVV3MYX3XB14JQG30FCDP1KA/operator-seat-rendered.png)
• Evidence: Rendered operator-seat.md (HTML) (local file: /var/folders/l8/htqy6t0j6hd9y084y1jqmqbr0000gn/T/no-mistakes-evidence/01KVV3MYX3XB14JQG30FCDP1KA/operator-seat.html)

Pipeline

Updates from git push no-mistakes

✅ **intent** - passed

✅ No issues found.

✅ **Rebase** - passed

✅ No issues found.

✅ **Review** - passed

✅ No issues found.

✅ **Test** - passed

✅ No issues found.

• git show --stat HEAD — confirmed the change is one new file, docs/operator-seat.md (+104 lines), no code
• grep keyword audit of docs/operator-seat.md — confirmed presence of CAPTAINS-INTENT, 5 Whys, helmsman, runway-guard, eight-hour/eight minutes origin, north star, tie-back test, blast radius, and the 'Straight talk' built-vs-target section
• Verified markdown structure: title + 5 well-formed ## sections, numbered/bulleted lists, inline code, bold/italic emphasis
• pandoc docs/operator-seat.md -f gfm -s — rendered to HTML with no warnings, confirming valid GFM
• Opened the rendered HTML in Chrome and captured a full-page screenshot to confirm the document displays cleanly end-to-end
• git status --short — worktree clean, no transient artifacts left behind

⚠️ **Document** - 1 info

• ℹ️ docs/operator-seat.md - docs/operator-seat.md is added with no inbound link from README.md, CONTRIBUTING.md, or any docs index (none exists). It is not factually out of sync with the code, but it is currently undiscoverable. Whether to link it — and where — is a judgment call: README is a curated overview and this is a first-person conceptual essay, so surfacing it should be the maintainer's decision rather than an automatic edit.

✅ **Lint** - passed

✅ No issues found.

✅ **Push** - passed

✅ No issues found.