chore: add migration/ bundle for cross-machine setup

Bundles state that lives OUTSIDE the xenia-rs repo so a fresh clone on
another machine can be brought up to identical configuration via
migration/setup.sh:

  - claude-memory/             ~/.claude/projects/-home-fabi-RE-Project-Sylpheed/memory/
                               (103 files, 1.1 MB - MEMORY.md + every
                                project_xenia_rs_*.md from audits
                                addis_signext through audit-058)
  - project-root/dot-claude/   <project-root>/.claude/settings.json
                               (Stop hook + permissions)
  - project-root/ppc-manual/   <project-root>/ppc-manual/
                               (PowerPC reference docs, 397 files, 3.7 MB)
  - project-root/run-canary.sh <project-root>/run-canary.sh
  - README.md                  Human-readable setup checklist
  - setup.sh                   Idempotent installer (also reclones
                               xenia-canary at pinned HEAD 6de80dffe)
  - MANIFEST.md                Per-file mapping + per-file-not-bundled
                               restoration recipe

Excluded from bundle (not shippable via git):
  - Sylpheed ISO (7.8 GB; copyright; manual copy required)
  - sylpheed.db (395 MB; regenerable from XEX via analysis tooling)
  - target/ build artifacts (rebuild on target)
  - audit-runs probe firehoses (.log/.stdout/.stderr ~11 GB; rerun if needed)
  - audit-runs memory dumps (.bin ~4.5 GB; rerun audit-026/027/029 if needed)
  - xenia-canary checkout (setup.sh reclones from
    git.mc02.dev/fabi/Xenia-Canary.git at HEAD 6de80dffe)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

migration/project-root/dot-claude/settings.json

@@ -0,0 +1,72 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash",
+      "Bash(cmake *)",
+      "Bash(apt-cache *)",
+      "Bash(cargo build *)",
+      "Bash(cargo clippy *)",
+      "Bash(cargo check *)"
+    ],
+    "deny": [
+      "Bash(git push*)",
+      "Bash(git push -f*)",
+      "Bash(git commit --no-verify*)",
+      "Bash(git commit -n*)",
+      "Bash(git config --global*)",
+      "Bash(sudo)",
+      "Bash(sudo *)",
+      "Bash(su)",
+      "Bash(su *)",
+      "Bash(doas *)",
+      "Bash(curl *)",
+      "Bash(wget *)",
+      "Bash(ssh *)",
+      "Bash(scp *)",
+      "Bash(rsync *)",
+      "Bash(nc *)",
+      "Bash(ncat *)",
+      "Bash(telnet *)",
+      "Bash(ftp *)",
+      "Bash(sftp *)",
+      "Bash(ping *)",
+      "Bash(rm -rf /)",
+      "Bash(rm -rf /*)",
+      "Bash(rm -rf ~)",
+      "Bash(rm -rf ~/*)",
+      "Bash(rm -rf $HOME*)",
+      "Bash(rm -rf .)",
+      "Bash(rm -rf ..)",
+      "Bash(rm -rf *)",
+      "Bash(dd *)",
+      "Bash(mkfs*)",
+      "Bash(fdisk *)",
+      "Bash(parted *)",
+      "Bash(mount *)",
+      "Bash(umount *)",
+      "Bash(shutdown*)",
+      "Bash(reboot*)",
+      "Bash(poweroff*)",
+      "Bash(halt*)",
+      "Bash(systemctl *)",
+      "Bash(service *)",
+      "Bash(crontab *)",
+      "Bash(iptables *)",
+      "Bash(chmod -R 777 *)",
+      "Bash(chown -R *)"
+    ]
+  },
+  "hooks": {
+    "Stop": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "n=0; for name in xenia_canary xenia-rs; do pids=$(pgrep -x \"$name\" 2>/dev/null || true); if [ -n \"$pids\" ]; then cnt=$(echo \"$pids\" | wc -l); n=$((n + cnt)); kill $pids 2>/dev/null; sleep 0.2; kill -9 $pids 2>/dev/null || true; fi; done; if [ \"$n\" -gt 0 ]; then printf '{\"systemMessage\":\"Stop hook killed %d stale xenia process(es)\"}' \"$n\"; fi",
+            "timeout": 5
+          }
+        ]
+      }
+    ]
+  }
+}