Rebuild Guide API reference around canonical OpenAPI shape

[PunchTheDev]

Summary

Restructures QuickstartGuide API reference section to match the canonical OpenAPI schema served by ${API_BASE_URL}/openapi.json. Adds 7 missing endpoints, switches path params from generic {id} to canonical {round_id} / {spec_id} / {contributor} / {submission_id}, and groups by intent instead of dumping a flat 14-row table.

Motivation

A first-timer scanning the table previously saw {id} everywhere — Swagger uses {round_id} / {spec_id} / {submission_id}, so copy-pasted curls wouldn't drop into the try-it-out console without rewriting. The table was also missing several pedagogically important endpoints (POST /eval/preview for scoring without recording, GET /submissions/{id}/step for fetching the STEP file, all /rounds variants), and intent was implicit. Live OpenAPI audit confirmed 21 canonical paths; the Guide previously documented 14.

Changes

• QuickstartGuide.tsx L744–826: API reference rebuilt with 7 intent groups (Rounds / Specs / SOTA / Leaderboards / Submissions / Eval / Health). Path params canonicalized. Swagger /docs link promoted from buried footer-line into a top-of-section callout card with hover tooltip.
• Endpoint count 14 → 21:
  • GET /rounds — all rounds (past + active)
  • GET /rounds/{round_id} — single round metadata
  • GET /submissions/{submission_id} — single submission detail
  • GET /submissions/{submission_id}/step — STEP file (3D viewer source)
  • POST /eval/preview — score an agent against one spec without recording (body: {agent_code, spec_id})
  • GET /health + GET /health/deep
• Descriptions rewritten to canonical OpenAPI vocabulary: "breadth-normalized percentile rank", "progressive history — one entry per moment the record improved", "STEP file", "Score an agent against one spec without recording".
• Step 2 (#explore) gains a ↓ full endpoint table cross-link before the curl block — closes the loop between the inline curl tutorial and the complete reference (step 281 cross-link pattern).
• BACKLOG L113 flipped ○ ○ ○ → ● ● ● with rationale.

Verification

Puppeteer at 1440×900 on /guide#api:

• 7 group headers render in order: Rounds, Specs (problems), SOTA, Leaderboards, Submissions, Eval, Health
• 21 endpoint rows
• No {id} generic path params remain
• All 7 newly-added canonical endpoints present
• Swagger callout box rendered with link to ${API_BASE_URL}/docs + 129-char tooltip
• Canonical-vocabulary strings present: "breadth-normalized", "Progressive history", "STEP file", eval-preview description

Puppeteer at 1440×900 on /guide#explore:

• 1 anchor link to #api with text "full endpoint table ↓"

0 new console errors (1 pre-existing 404 on a tile resource — unchanged baseline).