phonics 1.4.0

This is the first CRAN release of phonics since 1.3.10.

Correctness

Reconciled every exported phonetic encoder with its primary or authoritative algorithm specification and added independent conformance cases for the documented rules.
Corrected user-visible output in Caverphone 2, Cologne, Match Rating comparison, original and USDA Modified NYSIIS, Phonex, Roger Root, Refined Soundex edge handling, and Census Modified Statistics Canada encoding. Examples include the Caverphone 2 initial-Y rule, Modified NYSIIS terminal and contextual rules, Roger Root’s encoding of Breschnew (09462), and Statistics Canada normalization of garçon when cleaning is disabled (GRCN).
Made all four ONCA variants explicit compositions of NYSIIS followed by Soundex, including the package’s modified and refined combinations.

Hardened the native C++ implementations against out-of-bounds lookaround, unsafe character indexing, and missing values, and removed the undefined (char)NULL sentinel behavior.
Repaired compilation and execution on Alpine Linux with musl libc and added regression protection for Metaphone GH boundaries.
Removed the unnecessary Boost usage and the BH package dependency.

Defined maxCodeLen as a single non-negative whole number wherever it is supported. Invalid, missing, fractional, non-finite, negative, and non-scalar values now fail with a package-owned diagnostic before reaching native or substring operations.
Cologne retains maxCodeLen = NULL as its historical unbounded default; explicit values now validate and truncate the result.
The USDA Modified NYSIIS variant now warns and returns NA for names ending in JR or SR, as required by its published input rules.
Corrected the advertised modified-ONCA dispatch path and all-NA Match Rating comparison behavior.

Migrated to testthat edition 3 and a conventional CRAN-executed test entry point.
Added algorithm-conformance, public-contract, integration, boundary, historical-regression, and broad fixture-based coverage across all exported functions and algorithm variants.

Completed a package-wide reference audit, committed reproducible roxygen output, and added an independent documentation-freshness check.
Corrected citations, algorithm authorities, argument contracts, examples, and the package reference material.