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/progress-debt-segmentation-guard.test.cjs

@@ -8,7 +8,7 @@
 // `query audit-uat` milestone-filters the ACTIVE tree but deliberately adds
 // ARCHIVED trees unfiltered (each result stamped `archived_milestone`), while
 // `summary.total_items` spans both populations. Reading that summary as
-// current-milestone debt made every /gsd-progress run present six shipped
+// current-milestone debt made every /msd-progress run present six shipped
 // milestones' worth of still-open items as CURRENT debt (49 reported vs 13
 // real). The fix counts non-archived results only and gives archived debt its
 // own labeled line — segmented, never hidden (an item archived still-open is
@@ -21,7 +21,7 @@ const assert = require('node:assert/strict');
 const fs = require('node:fs');
 const path = require('node:path');
 
-const PROGRESS_MD = path.join(__dirname, '..', 'gsd-core', 'workflows', 'progress.md');
+const PROGRESS_MD = path.join(__dirname, '..', 'msd-core', 'workflows', 'progress.md');
 
 // progress.md is shipped workflow text — the bytes ARE what the runtime
 // loads, so a structural scan over it tests the deployed contract (same