[Repo Assist] Fix CSV schema parsing: column names containing parentheses corrupt type annotation

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Closes #946

Problem

When a CSV Schema parameter includes a column whose name contains parentheses, the type annotation is corrupted. For example:

// Schema="Na(  )me (int)"
// Expected: name = "Na(  )me", type = int
// Actual:   name = "Na",       type = " )me (int"  ← WRONG

This was reported in #946 in 2016 and confirmed as reproducible.

Root Cause

CsvInference.fs line 39 defined nameAndTypeRegex with RegexOptions.RightToLeft:

lazy Regex(@"^(?(name).+)\((?(type).+)\)$", RegexOptions.Compiled ||| RegexOptions.RightToLeft)

In RightToLeft mode, the regex engine starts from the right end of the string and scans leftward. When the column name contains a ( character, the greedy .+ for the type group sweeps past the intended (type) boundary and instead anchors the \( separator on the first ( in the string — giving a completely wrong parse.

Fix

Remove RegexOptions.RightToLeft from nameAndTypeRegex. Without it, the standard left-to-right greedy engine correctly backtracks the name .+ until the trailing (type) pattern matches — always landing on the last (...) at the end of the string, which is the intended semantics.

Note: overrideByNameRegex retains RightToLeft intentionally, as that pattern must find the last -> or = separator when the column name may contain those characters.

Test

Added a regression test Column name with parentheses is parsed correctly in schema to InferenceTests.fs.

Test Status

• Build passes (dotnet build src/FSharp.Data.Csv.Core/)
• FSharp.Data.DesignTime.Tests pass — 49/49 inference tests pass (includes new regression test)
• FSharp.Data.Tests could not be built: the WorldBank type provider requires network access to api.worldbank.org, which is blocked by the build environment's network proxy. This is unrelated to this change.

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