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/lint-source-test-name-collision.cjs

@@ -11,7 +11,7 @@
  * test) whose filename happened to match Node's `test-*` collection
  * convention. `scripts/run-tests.cjs` — what local `npm test` and GitHub CI
  * use — globs only `tests/**\/*.test.cjs`, so CI never saw it. But the
- * REMOTE test runner (the push gate; see CLAUDE.md's `gsd-test` section)
+ * REMOTE test runner (the push gate; see CLAUDE.md's `msd-test` section)
  * collects test files the way `node --test` does by default, across the
  * whole tree, so it picked the file up and executed it AS a test, where it
  * exited 1. Net effect: `next` was green on GitHub CI and red on the push
@@ -42,20 +42,20 @@
  *
  * ## Scanned (source/shipped) directories
  *
- *   src/, scripts/, hooks/, bin/, gsd-core/bin/ (excluding
- *   gsd-core/bin/lib/**, see below), eslint-rules/
+ *   src/, scripts/, hooks/, bin/, msd-core/bin/ (excluding
+ *   msd-core/bin/lib/**, see below), eslint-rules/
  *
  * ## Exempted
  *
  *   - tests/ — files there are SUPPOSED to match; that is the point.
  *   - node_modules/, .git/ — never source we own.
- *   - gsd-core/bin/lib/** — build output generated from src/*.cts by
+ *   - msd-core/bin/lib/** — build output generated from src/*.cts by
  *     `npm run build:lib` (tsc), and gitignored (verified: every file under
  *     it, including the incident's own post-fix
- *     `gsd-core/bin/lib/real-home-guard.cjs`, is listed in .gitignore). A
+ *     `msd-core/bin/lib/real-home-guard.cjs`, is listed in .gitignore). A
  *     generated file inherits its source's basename 1:1, so scanning it
  *     would double-report the exact same defect `src/` already caught —
- *     noise, not signal. `gsd-core/bin/shared/*.json` is data, not code,
+ *     noise, not signal. `msd-core/bin/shared/*.json` is data, not code,
  *     but is harmlessly included since it never matches a JS/TS extension.
  *
  * Exported pure(ish) function `checkSourceTestNameCollisions({ dirs, root })`
@@ -92,20 +92,20 @@ const BASENAME_PATTERNS = [
 /**
  * Source/shipped directories this guard checks, relative to repo root.
  * Confirmed against the repo layout: src/, scripts/, hooks/, bin/,
- * gsd-core/bin/, eslint-rules/ all ship first-party source or shipped
+ * msd-core/bin/, eslint-rules/ all ship first-party source or shipped
  * tooling; nothing else at the top level carries executable source outside
  * tests/.
  */
-const DEFAULT_SCAN_DIRS = ['src', 'scripts', 'hooks', 'bin', 'gsd-core/bin', 'eslint-rules'];
+const DEFAULT_SCAN_DIRS = ['src', 'scripts', 'hooks', 'bin', 'msd-core/bin', 'eslint-rules'];
 
 // Directories to never descend into anywhere in the tree.
 const ALWAYS_EXCLUDE_DIR_NAMES = new Set(['node_modules', '.git']);
 
 // Relative dir prefixes (POSIX-joined, relative to repo root) that are
 // generated build output and must not be scanned — see the module doc for
-// why gsd-core/bin/lib is excluded (it 1:1-inherits src/*.cts basenames, so
+// why msd-core/bin/lib is excluded (it 1:1-inherits src/*.cts basenames, so
 // scanning it double-reports the same defect src/ already catches).
-const GENERATED_OUTPUT_PREFIXES = ['gsd-core/bin/lib'];
+const GENERATED_OUTPUT_PREFIXES = ['msd-core/bin/lib'];
 
 function toPosix(p) {
   return p.split(path.sep).join('/');