docs: competitive landscape — US farm software (2026-05)

[dnplkndll]

What changed

Adds docs/competitive-landscape.md — the first merged competitive-analysis pass for farm-pack. No code touched.

Why

We had positioning intent in memory (US SMB Odoo + farm vertical, four jobs) but no head-to-head against the products a real US small farmer evaluates today. This file is the durable reference so the next contributor (or designer, or marketing pass) doesn't have to re-fetch and re-synthesize.

What's in it

• Snapshot of what farm-pack has built today, including the just-shipped v1 geo slice.
• Profiles of Ambrook, Traction Ag, FarmRaise, FieldEdge, plus the UW-Extension buyer's-guide products (Quicken, QuickBooks, CenterPoint Ag, EasyFarm, Farm Biz, PcMars) and the Agritecture D2C-logistics thinkpiece.
• Four-band coverage matrix (bookkeeping / production records / commerce / logistics). farm-pack is the only entry crossing all four for the SMB segment — that's the wedge.
• Three fast-followable feature gaps: variable-weight billing, customer-self-service subscription pause/skip, receipt OCR on bills.
• Two explicit don't-chase zones: grant/program reporting (FarmRaise's moat) and grain marketing (Traction Ag's specialization).
• Visual brand reference for the eventual marketing site: Ambrook-style rural-Americana, not generic SaaS purple.

Caveats called out in the doc

• Traction Ag's page returned 403; that profile is from general knowledge — verify before quoting publicly.
• No pricing intel scraped (would need partner-call notes or trial signups).

Test plan

• doc renders cleanly on the GitHub PR page (no broken table, no rogue characters)