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/quick-batch.property.test.cjs

@@ -4,9 +4,9 @@
  * quick-batch.property.test.cjs — Property-based tests for quick-batch core
  * primitives (#3675, epic #3344, ADR-1239 "Quick-batch binding").
  *
- * Module: gsd-core/bin/lib/quick-batch.cjs (compiled from src/quick-batch.cts)
+ * Module: msd-core/bin/lib/quick-batch.cjs (compiled from src/quick-batch.cts)
  *
- * Test matrix rows covered (`.gsd/phase/feat-3675-quick-batch-core-primitives/50-test-matrix.md`):
+ * Test matrix rows covered (`.msd/phase/feat-3675-quick-batch-core-primitives/50-test-matrix.md`):
  *   parser — parseTaskList round-trips any valid bulleted task list (CLAUDE.md
  *            "Property-Based Testing: Parsers... must include at least one
  *            fast-check property test")
@@ -35,7 +35,7 @@ const {
   resumeBatch,
   completeQuickItem,
   updateBatchItems,
-} = require('../gsd-core/bin/lib/quick-batch.cjs');
+} = require('../msd-core/bin/lib/quick-batch.cjs');
 const { makeFakeClock } = require('./helpers/clock.cjs');
 const { cleanup } = require('./helpers.cjs');