fix(fmt): delegate component expression formatting to markup_fmt (#29763)
Closes #26999
This PR now solves component expression formatting by delegating
parsing/formatting to `markup_fmt` instead of using Deno-side regex
placeholder preprocessing.
## What changed
- upgraded `markup_fmt` and aligned Deno formatter config with the newer
API
- removed local `format_expressions_in_text(...)` preprocessing/restore
pipeline
- routed component formatting through `markup_fmt` as the single
parser/formatter source of truth
- updated Svelte/Vue fixtures and related fmt expectations to current
formatter output
- preserved Jinja/Nunjucks pseudo-block text in callback handling to
avoid invalid JS formatting attempts
## Why this approach
Earlier review feedback called out regex preprocessing as fragile (for
example formatting inside comments). This version avoids that class of
issues by relying on `markup_fmt`'s native parse tree and language-aware
formatting behavior.
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Co-authored-by: Bartek IwaĆczuk <biwanczuk@gmail.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>