Mechanical rename produced by scripts/msd-rename.cjs: gsd/Gsd/GSD -> msd/Msd/MSD
across contents and paths, upstream package/repo coordinates -> @golem15/msd-core
and golem15com/msd-core. Deep links into upstream history, sibling upstream
packages, the GSD-2 import feature, CHANGELOG.md and .changeset/ are kept as-is.
Hand edits on top: MSD block-letter banner and logos, LICENSE copyright line,
package/plugin identity, regenerated lockfile, install-tree fixtures, derived
registries and benchmark baseline; migration checksum baseline re-locked
(MSD keeps its own install state, so no install had applied the old sums);
sort-order and regex-escaped expectations in tests adjusted.
`cmdVerifyKeyLinks` compiled `must_haves.key_links[].pattern` from plan frontmatter with `new RegExp()` and tested it against whole file contents, so a nested-quantifier pattern such as `(a+)+$` hung `verify-phase` indefinitely (CWE-1333). JavaScript has no regex-execution timeout.
Untrusted patterns now run on RE2 (re2js), whose match time is linear in input length — the class is closed by the engine, not by a heuristic screen. The screen lost in the ADR-0174 consolidation was deliberately NOT restored: it never worked, since `(a|a)*$`, `((a+))+$`, `(a+){2,}$` and `(a{1,3})+$` all evade it. A refused pattern's matcher returns false for every input, so it cannot report a match no matter what the caller does.
The engine is vendored at gsd-core/bin/lib/vendor/re2js.cjs because gsd-core/bin/** is copied into installed trees with no node_modules; runtime dependencies are unchanged. New ESLint rule local/no-external-require-in-bin enforces that invariant, which had been documented in a comment since the #3024/#2071 bug class and enforced nowhere.
Backreferences and look-around are unsupported by RE2 by construction — disclosed in a Changed changeset.
Closes#3477
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>