figure-agent v0.1.7.1

Hardening release driven by the 4-agent mid-review of v0.1.7 before its first remote push.

Findings: non-string YAML scalars crashed the strip with TypeError, all-HTML-comment input silently fell back without a warning, the fallback string was prose an LLM might mis-read, and the priority-order paragraph was placed after the user-supplied content.

Fixed

• scripts/llm_author_prompt.py _coerce_selection_notes helper: warns to stderr (naming the example dir and encountered type) and coerces to str when selection_notes is non-string (int, list, dict, bare YAML date such as 2026-04-29).
• scripts/llm_author_prompt.py: warn to stderr when selection_notes is non-empty before HTML-comment stripping but reduces to empty afterward.
• scripts/llm_author_prompt.py: shorten the missing-key fallback from prose "(none — only preview filename selected)" to "(none)" for parity with selected_preview and the briefing _section_body (empty) sentinel.

Changed

• prompts/llm_author_tikz.md: priority-order paragraph is now placed before the {{selection_notes}} placeholder so the LLM absorbs the precedence rule before reading user content.
• prompts/llm_author_tikz.md: priority paragraph extended to cover the extension pattern (selection notes adding visual detail consistent with §6) — the dogfood fig3_trap_schematic_v97/spec.yaml shows this is the real common pattern, not contradiction.

Tests

• Three regression tests in tests/test_llm_author_prompt.py: non-string coercion, empty-after-strip warning, priority paragraph survival.

108 pytest pass (105 → 108), ruff clean.

See CHANGELOG.md for the v0.1.7 entry that introduced selection_notes plumbing, and docs/roadmap-v0.1.7-selection-notes.md for the full audit-driven design rationale.