[FEATURE] Hebrew (RTL) caption support

Problem

OpenCut's captions currently don't properly support Hebrew. Hebrew is a right-to-left (RTL) language, and editors that assume left-to-right (LTR) text tend to:

• Render Hebrew captions with incorrect text direction / alignment (text reads left-aligned or visually reversed instead of right-aligned RTL).
• Mishandle mixed-direction lines (e.g. Hebrew with embedded Latin words, numbers, or punctuation), where the bidirectional (BiDi) algorithm isn't applied and segments end up in the wrong order.
• Place punctuation and line breaks on the wrong side.

This makes OpenCut hard to use for Hebrew-speaking creators who want to add subtitles/captions to their videos.

Solution

Add first-class Hebrew caption support, including:

• RTL rendering: detect/allow RTL text direction for caption blocks and render Hebrew right-aligned with correct base direction.
• Proper BiDi handling: apply the Unicode bidirectional algorithm so mixed Hebrew + Latin/number content displays in the correct visual order.
• Per-caption direction control: a way to set text direction (auto / LTR / RTL) on a caption or caption track, with auto detecting RTL from the text.
• Export correctness: ensure exported/burned-in captions and any exported subtitle formats (e.g. SRT/VTT) preserve the correct direction so they display correctly in other players.
• Font support: confirm the default caption font(s) include Hebrew glyphs, or allow selecting one that does.

Alternative

• Manually pre-formatting Hebrew text (e.g. inserting Unicode RTL/LRM control characters) before pasting — fragile and unfriendly for non-technical users.
• Burning captions externally in another tool and importing the rendered video — defeats the purpose of editing captions in OpenCut.

Anything else?

This would also lay groundwork for other RTL languages such as Arabic and Persian, since they share the same RTL/BiDi requirements. Happy to provide test clips with Hebrew captions if helpful.

No files, tests, or entry points are named in the issue. Start by locating caption rendering, direction controls, subtitle export, and caption font handling. Done means Hebrew and mixed Hebrew/Latin captions render and export correctly with auto, LTR, and RTL direction options.