fix: handle inner quotes in double-quoted env values in .env file (#32930)
## Summary
- Fix `--env-file` parsing of double-quoted values containing inner
(unescaped) quotes, e.g. `KEY="foo'bar"baz`qux"`
- Fix `\n` escape expansion in double-quoted values with inner quotes,
e.g. `KEY="foo\ni am "on" newline"`
**Root cause**: `find_char` found the first matching `"` after the
opening
quote, which was an inner quote — truncating the value. The dotenv npm
package instead treats the outermost quotes as delimiters.
**Fix**: New `find_closing_quote` function tries the nearest matching
quote first. If there's non-whitespace content after it on the same
line, inner quotes are present — it falls back to the last matching quote on
the line instead.
Closes #32928
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Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>