Fix CRAN issue "lost braces"

[louisaslett]

This pull request implements a fix for the "Lost braces" issues detected in the package documentation (.Rd files) by R CMD check and flagged by CRAN (see https://cran.r-project.org/web/checks/check_results_mlrMBO.html)

Summary of Changes

• Corrected improperly escaped braces in .Rd files and/or regenerated documentation via roxygen2.
• Removed disallowed trailing full stops from titles.
• Fixed imbalanced braces in multiple files which caused incorrect rendering.
• Fixed stray braces in setMBOControlMultiObj.R which caused references not to render.
• Verified fixes with tools::checkRd()

Context

This task was proposed by R Core developer Kurt Hornik as part of an initiative to improve CRAN package documentation. Packages with public repositories (GitHub, GitLab, Bitbucket) and a higher number of reverse dependencies were prioritised. This PR has been completed as part of an R Dev Day at the University of Warwick on 12 Sept 2025 (see r-devel/r-dev-day#110), although I also fixed all additional Rd issues which were thrown.

Suggested next steps

• Merge this PR to incorporate the fixes.
• Monitor subsequent CRAN checks to confirm the NOTE does not reappear.
• The following can be used to identify the issues with the documentation: list.files("man", full.names = TRUE) |> sapply(tools::checkRd). This PR resolves all issues that this check raises.