feat(tui): Full RTL/Bidi support for Persian, Arabic, Hebrew, and Urdu text

Problem

Persian, Arabic, Hebrew, and Urdu text renders left-aligned with disconnected letters in the Hermes TUI (hermes --tui). This makes the TUI unusable for ~500M+ potential users across Iran, the Middle East, North Africa, Pakistan, and Israel.

Currently:

• 🇮🇷 Chat messages render LTR (left-aligned) regardless of content
• 🔤 Persian/Arabic script letters are disconnected (isolated forms instead of cursive)
• 📌 Gutter glyph (▸ / ⚕) stays fixed on left for all languages
• ⌨️ Input field has no RTL cursor direction support
• 📝 Markdown blocks ignore text direction

Proposed Solution

Phase 1: Chat Message RTL (MVP)

• Detect RTL text via Unicode range (\u0600-\u06FF Arabic/Persian, \u0590-\u05FF Hebrew, \u0750-\u077F Arabic Supplement)
• Apply flexDirection: "row-reverse" for RTL message rows
• Apply alignItems: "flex-end" for RTL message content
• Mirror gutter glyph spacing for RTL

Phase 2: Full Bidi

• RTL cursor movement in input field when typing RTL text
• Per-paragraph direction detection in markdown renderer
• RTL tool output previews
• RTL system messages

Phase 3: Configuration

• display.rtl_enabled: true/false in config.yaml
• Auto-detect vs. force-LTR toggle

Implementation Notes

The fix is straightforward — a working prototype already exists as a local patch:

1. Add RTL detection regex to messageLine.tsx
2. Insert flexDirection={rtl ? 'row-reverse' : 'row'} on the message row
3. Add alignItems={rtl ? 'flex-end' : 'flex-start'} on the content box

Impact

• Iran: ~90M Persian speakers
• Arab world: ~400M Arabic speakers
• Israel: ~9M Hebrew speakers
• Pakistan: ~230M (Urdu uses Arabic script)
• Afghanistan: ~40M (Dari/Pashto)

Related Issues

• docs(web): document dashboard RTL chat limits #29069 — Web dashboard RTL chat limits
• feat(web/i18n): add Arabic (العربية) with full RTL layout support #29795 — Arabic RTL for web dashboard
• Feature Request: Add i18n / Multi-language UI support for CLI interface #12375 — CLI i18n/multi-language
• test(ink): add bidi regression coverage for mixed Arabic/English text #15238 — Bidi regression tests for Ink