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.

tests/adr-parser.unit.test.cjs

@@ -4,7 +4,7 @@
 /**
  * Example-based unit tests for adr-parser.cjs
  *
- * Target: gsd-core/bin/lib/adr-parser.cjs
+ * Target: msd-core/bin/lib/adr-parser.cjs
  * Purpose: kill surviving mutants by asserting EXACT values from every branch
  *
  * Gap coverage:
@@ -29,7 +29,7 @@ const {
   parseAdrMarkdown,
   shouldRejectAdrStatus,
   CANONICAL_HEADERS,
-} = require('../gsd-core/bin/lib/adr-parser.cjs');
+} = require('../msd-core/bin/lib/adr-parser.cjs');
 
 // ─────────────────────────────────────────────────────────────────────────────
 // normalizeAdrHeader — exact transformation chain