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.

scripts/setup-branch-protection.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # setup-branch-protection.sh
 #
-# Apply branch protection rules to `main` and `next` for the GSD repo.
+# Apply branch protection rules to `main` and `next` for the MSD repo.
 # Idempotent — run as many times as you like. Re-running brings the live
 # rules back to what this script declares, so the script IS the source of
 # truth for branch protection.
@@ -13,7 +13,7 @@
 #   DRY_RUN=1 bash scripts/setup-branch-protection.sh   # show payloads, don't apply
 #
 # Requirements:
-#   - gh CLI authenticated against open-gsd/gsd-core with admin scope
+#   - gh CLI authenticated against golem15com/msd-core with admin scope
 #   - jq installed
 #
 # What it sets:
@@ -49,7 +49,7 @@
 
 set -euo pipefail
 
-REPO="${REPO:-open-gsd/gsd-core}"
+REPO="${REPO:-golem15com/msd-core}"
 DRY_RUN="${DRY_RUN:-0}"
 
 # Required status checks. Adjust as your CI suite evolves.