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.

capabilities/pattern-mapper/capability.json

@@ -9,7 +9,7 @@
     "research"
   ],
   "engines": {
-    "gsd": ">=1.6.0"
+    "msd": ">=1.6.0"
   },
   "runtimeCompat": {
     "supported": [
@@ -19,7 +19,7 @@
   },
   "skills": [],
   "agents": [
-    "gsd-pattern-mapper"
+    "msd-pattern-mapper"
   ],
   "hooks": [],
   "config": {
@@ -33,7 +33,7 @@
     {
       "point": "plan:pre",
       "ref": {
-        "agent": "gsd-pattern-mapper"
+        "agent": "msd-pattern-mapper"
       },
       "fragment": {
         "path": "fragments/plan-pre.md"