fix(virtues): add body-text auto-shrink for vertical overflow (#190)

[jsboige]

Problem

Virtues cards (and potentially other CardSets) have text that overflows vertically — the .texte container has overflow: hidden, so text is silently clipped. Issue #190 tracks this.

Worst FR offenders: Argument pertinent (178 ch), Arguments vertueux (167 ch), Distance emotionnelle adequat (143 ch). All languages affected — RU Cyrillic ~15-20pct wider.

Solution

Extends the proven title auto-shrink (PR #400, issue #316) to vertical body text overflow:

• New autoFitBodyText() in frame.js: binary search on font-size for .desc_* and .exemple_* children of .texte container
• Stops when scrollHeight lessThanOrEqual clientHeight (2px tolerance, matching OverflowDetector.cs)
• No-op when text fits (common case) — same idempotent design as title shrink
• Min font floor: 7px (readable at print DPI)
• All cards generically, language/CardSet agnostic

Scope

• frame.js only — +70 lines (new function + call)
• No C#, template, or CSV changes

Validation

• JS syntax valid (Node.js parse)
• dotnet build: 0 errors
• 131/131 unit tests pass
• QA visuelle requise (ai-01 Playwright+vision) avant merge

Co-Authored-By: Claude Opus 4.8 noreply@anthropic.com

[jsboige]

ai-01 Code Review — APPROVE (pending QA visuelle)

Code review OK — clean extension of #400 title auto-shrink pattern to body text.

Verified

• Binary search (10 iters, factor-based) converges quickly
• No-op when text fits (common case)
• Idempotent reset to natural sizes before calc
• 2px tolerance matches OverflowDetector.cs
• Floor 7px readable at print DPI
• 131/131 tests pass, dotnet build clean
• Scope: 1 file (frame.js), +70/-1

One cosmetic note

The selector hardcodes .desc_XX / .exemple_XX for 8 langs. Could use attribute selectors for future-proofing, but matches existing title-shrink pattern — not blocking.

Before merge

QA visuelle on a Virtues card with long text (e.g. Argument pertinent 178ch FR) to confirm body text auto-shrinks instead of clipping.