fix(dsh): O-2 — WARN и в install_global, ассерты артефактов (#62)

dsh/install.sh

@@ -372,6 +372,7 @@ check() {
 }
 
 install_global() {
+  warn_mixed_dsh_home
   mkdir -p "$DSH_HOME"
   local target="$DSH_HOME/AGENTS.md"
   if [ -f "$target" ]; then

dsh/tests/install.test.mjs

@@ -666,6 +666,21 @@ test('--skills and --roles warn when DSH_HOME exists while HOME is isolated (O-2
     const rolesOut = roles.stdout + roles.stderr
     assert.equal(roles.status, 0, rolesOut)
     assert.ok(rolesOut.includes(warn), rolesOut)
+    assert.ok(existsSync(join(sharedDsh, 'roles', 'dev.md')), 'roles land in the warned DSH_HOME')
+
+    // --global overwrites AGENTS.md (after a backup): the destructive step must
+    // warn too (T3.1).
+    const global = runInstaller(home, ['--global'], { DSH_HOME: sharedDsh })
+    const globalOut = global.stdout + global.stderr
+    assert.equal(global.status, 0, globalOut)
+    assert.ok(globalOut.includes(warn), globalOut)
+    assert.ok(existsSync(join(sharedDsh, 'AGENTS.md')), 'AGENTS.md is installed after the warning')
+
+    // One run touching several steps warns exactly once (T3.2).
+    const combined = runInstaller(home, ['--skills', '--roles', '--superpowers-from', src], { DSH_HOME: sharedDsh })
+    const combinedOut = combined.stdout + combined.stderr
+    assert.equal(combined.status, 0, combinedOut)
+    assert.equal((combinedOut.match(/WARN: DSH_HOME=/g) ?? []).length, 1, combinedOut)
 
     // Isolated together ($DSH_HOME=$HOME/.dsh): no warning.
     const normal = runInstaller(home, ['--skills', '--superpowers-from', src])