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/how-to/command-exit-zero-gate.md

@@ -30,7 +30,7 @@ the project root as its cwd and the inherited process environment.
 
 ```bash
 # Example: a bundled check script shipped with the capability
-node "${GSD_CAP_DIR}/checks/pre-ship.js"
+node "${MSD_CAP_DIR}/checks/pre-ship.js"
 ```
 
 You may interpolate three loop-context placeholders directly into the command:
@@ -58,7 +58,7 @@ config key with `when`:
       "check": {
         "predicate": {
           "kind": "command-exit-zero",
-          "command": "node \"${GSD_CAP_DIR}/checks/pre-ship.js\" \"${PHASE_DIR}\"",
+          "command": "node \"${MSD_CAP_DIR}/checks/pre-ship.js\" \"${PHASE_DIR}\"",
           "timeout": 30
         }
       },
@@ -95,7 +95,7 @@ You can run the evaluator standalone to verify your predicate before wiring it
 into a loop point:
 
 ```bash
-gsd_run check predicate \
+msd_run check predicate \
   --predicate '{"kind":"command-exit-zero","command":"node checks/pre-ship.js \"${PHASE_DIR}\"","timeout":30}' \
   --phase-dir ".planning/phases/03-my-phase" \
   --phase-number "03" \
@@ -122,7 +122,7 @@ at your chosen point. The workflow gate-dispatch (`execute:wave:post`,
 dispatches the evaluator automatically — no further wiring needed.
 
 ```bash
-gsd_run loop render-hooks ship:pre --raw
+msd_run loop render-hooks ship:pre --raw
 ```
 
 ## Gotchas
@@ -136,7 +136,7 @@ gsd_run loop render-hooks ship:pre --raw
 - **Output is trimmed.** Only the last 2000 chars of stderr/stdout surface in
   the gate `message`. Emit a concise diagnostic; don't rely on grepping long
   output downstream.
-- **Env is inherited.** The command sees the full GSD process environment. Do
+- **Env is inherited.** The command sees the full MSD process environment. Do
   not put secrets in the command string; read them from env or a file like any
   shell script.