Bug: Incorrect Hindi (Devanagari) text shaping/rendering (Short 'i' matra issue)

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Environment

- OS:
- Python:
- BabelDOC:

Describe the bug

Hi team,

I am using pdf2zh-next, which relies on BabelDOC for PDF generation, and I noticed a critical rendering bug with Hindi (Devanagari script) translations.

Expected Behavior

Hindi requires Complex Text Layout (CTL). For example, the short 'i' matra (ि) must visually render before the consonant it modifies. The word should look like this: विचार

Actual Behavior

The text is being drawn in its raw logical sequence without shaping. The matra is appearing after the consonant. It renders incorrectly like this: वचिार (and similar issues happen with words like मित्र -> मत्रि).

Steps to Reproduce

1. Translate an English PDF to Hindi using BabelDOC as the backend.
2. Check the generated bilingual/mono PDF output. Words with the short 'i' matra (and other complex conjuncts) are visually broken.

Suggested Cause

It seems the text shaping engine (e.g., uharfbuzz) is either not being applied to Indic scripts, or PyMuPDF is inserting the raw text strings without proper OpenType GSUB/GPOS table processing for the fallback font.

Screenshots

Steps to Reproduce

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Expected Behavior

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Relevant Log Output or Screenshots

Original PDF File

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Additional Context

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