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.

commands/msd/pause-work.md

@@ -0,0 +1,44 @@
+---
+name: msd:pause-work
+description: Create context handoff when pausing work mid-phase
+argument-hint: "[--report]"
+allowed-tools:
+  - Read
+  - Write
+  - Bash
+  - Grep
+requires: [phase, progress]
+---
+
+<objective>
+Create `.continue-here.md` handoff file to preserve complete work state across sessions.
+
+Routes to the pause-work workflow which handles:
+- Current phase detection from recent files
+- Complete state gathering (position, completed work, remaining work, decisions, blockers)
+- Handoff file creation with all context sections
+- Git commit as WIP
+- Resume instructions
+</objective>
+
+<execution_context>
+@~/.claude/msd-core/workflows/pause-work.md
+</execution_context>
+
+<context>
+State and phase progress are gathered in-workflow with targeted reads.
+</context>
+
+<process>
+If `--report` is in $ARGUMENTS:
+Read and execute `~/.claude/msd-core/workflows/session-report.md` end-to-end.
+
+**Follow the pause-work workflow**.
+
+The workflow handles all logic including:
+1. Phase directory detection
+2. State gathering with user clarifications
+3. Handoff file writing with timestamp
+4. Git commit
+5. Confirmation with resume instructions
+</process>