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.

docs/features/windsurf-runtime-support.md

@@ -4,14 +4,14 @@ title: Windsurf Runtime Support
 group: v1.29 Features
 ---
 
-**Part of:** `npx @opengsd/gsd-core`
+**Part of:** `npx @golem15/msd-core`
 
-**Purpose:** Add Windsurf as a supported AI CLI runtime for GSD installation and execution.
+**Purpose:** Add Windsurf as a supported AI CLI runtime for MSD installation and execution.
 
 **Requirements:**
 - REQ-WINDSURF-01: Installer MUST detect Windsurf runtime and offer it as a target
-- REQ-WINDSURF-02: GSD commands MUST function correctly within Windsurf sessions
+- REQ-WINDSURF-02: MSD commands MUST function correctly within Windsurf sessions
 
 **Process:**
 1. **Detect** — Identify Windsurf runtime availability on the system
-2. **Install** — Configure GSD skills and hooks for the Windsurf environment
+2. **Install** — Configure MSD skills and hooks for the Windsurf environment