Frame Guide Step 1 by canonical Docker vs Native paths

[PunchTheDev]

Summary

Step 1 — Set up was muddled: "Docker is the easiest path" in the lead, but the code block showed pip install -e . (CLI only, no FEA stack), and Docker was relegated to a footnote. First-timers couldn't tell which path they were on.

This aligns the Guide vocabulary with forge check-deps (forge/cli.py L1136–1190), which already exposes the canonical two-paths model: Option A — Docker (recommended) vs Option B — Native toolchain. Lead names both paths inline, the CLI flow stays one code block, and forge check-deps is framed as the diagnostic that confirms which path is ready.

Changes

• QuickstartGuide.tsx L467–501: Step 1 lead rewritten to surface both paths verbatim from check-deps; existing CalculiX/gmsh/OCP tooltips preserved.
• Code block comment changed from # Verify your setup → # Confirms which path is ready — Docker, Native, or both.
• Footnote rewritten to promote forge eval --docker for first-timers with a new tooltip on --docker naming the forge-eval CI image (so the local↔leaderboard parity is explicit).
• BACKLOG.md: bundled "Step 1–5" row split into 5 individual rows (matches the split started in Frame Guide Step 2 with CLI vs API roles and filter hints #295); Step 1 flipped ○ ○ ○ → ● ● ● with the rationale.

Test plan

• npm run build clean
• Puppeteer 1440×900 /guide#setup: lead contains both Option A and Option B strings; 4 tooltips (CalculiX 78 / gmsh 91 / OCP 107 / --docker 147 chars); code block contains forge check-deps + Docker, Native, or both comment; first-timer footnote present; 0 new console errors.