refactor: hard-fork GSD -> MSD (Make Software Done)

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.

docs/how-to/resolve-eslint-coverage-findings.md

@@ -66,7 +66,7 @@ The `reason` is **structurally required** — an entry with a missing, empty, or
 
 ⚠️ **"Not linted yet" is not a reason.** An allowlist entry meaning *we will get to it* is a TODO wearing an exemption's badge, and it will outlive everyone who remembers it. If the file should eventually be linted, lint it now.
 
-A file that is **explicitly ignored** — the `gsd-core/bin/lib/**` tsc artifacts under ADR-457 — needs no allowlist entry. Ignored is a recorded decision; unmatched is an accident. The guard already tells them apart.
+A file that is **explicitly ignored** — the `msd-core/bin/lib/**` tsc artifacts under ADR-457 — needs no allowlist entry. Ignored is a recorded decision; unmatched is an accident. The guard already tells them apart.
 
 Note that `bin/install.js` also needs no entry: it resolves to two rules under ADR-1703's deliberately minimal coverage, which is non-empty and therefore passes.