Fix CRAN issues, add test suite, and fix correctness bugs

[ehsanx]

Resolves the three CRAN reviewer issues and hardens the package with a real test suite and several correctness fixes. R CMD check --as-cran --run-donttest is clean (0 errors, 0 warnings, 1 expected dev-version NOTE).

CRAN compliance:

• DESCRIPTION: add method references with 9 verified DOIs/ISBN; bump to 0.14.1.9000.
• pipe.Rd: add \value (was the only missing \value tag).
• Convert all 7 \dontrun examples to \donttest on the bundled nhanes_mortality data (examples no longer need the NHANES Suggests pkg).
• Strengthen every \value to name the actual runtime class and meaning (e.g. svypooled is c("kableExtra","knitr_kable")).

Correctness fixes:

• svygof: attach decile groups to the existing design via stats::update() instead of rebuilding a bare svydesign; preserves fpc/calibration and now works on replicate designs (previously errored). Fix the example, which called svyAUC, and the @param design doc.
• svyAUC: replace hardcoded 1.96 with a design-df qt() critical value and build the CI on the logit scale so it stays within [0,1]; remove dead code.
• svycoxph_CE_mi: default time_var/status_var followup/death -> stime/status (the old defaults did not exist in the bundled data).
• svytable1: error on a 0-row design instead of returning a fake table; stop flooring the design effect at 1 (was over-suppressing deff<1 cells).
• README: rewrite to the real APIs on bundled data (the Cox and plotint examples documented signatures that do not exist); every snippet verified.

New functionality:

• svykmplot gains an se argument (default TRUE). se = FALSE skips the slow survey-weighted CI bands (28s -> 0.3s on the example data).

Testing & hygiene:

• Replace the trivial smoke test with a real testthat suite: 67 passing assertions across descriptive tables, diagnostics, additive interaction (tightly pinned pure-math RERI/AP/S), survival, and MI pooling, rooted on the bundled data with edge-case coverage.
• Clean up .data$ usage inside tidyselect verbs (removes ~258 deprecation warnings); gate addintlist progress messages behind verbose.
• Untrack R/.Rhistory; ignore *.Rhistory and Rplots.pdf; fix URL trailing slash; keep NEWS.md/cran-comments.md out of the *.md gitignore.