Add MPQ verify modes, harden CI assertions, fix CRLF/docstring

- mpqpack gains --list and --cat (StormLib-backed) for reading archives back
- CI now asserts the archive lists the expected file and that version
  substitution landed inside the MPQ, not just that a file exists
- Dockerfile strips CRLF from entrypoint/package so local Windows builds work
- drop invalid escape in package.py docstring

.gitea/workflows/ci.yml

@@ -28,8 +28,16 @@ jobs:
             -v "$PWD/test:/work" \
             mpq-packager:ci
 
-      - name: Assert artifact exists
+      - name: Assert archive is valid and contains the expected file
         run: |
           set -euo pipefail
           test -s test/dist/patch-Z.mpq
-          echo "OK: $(stat -c%s test/dist/patch-Z.mpq) bytes"
+          echo "size: $(stat -c%s test/dist/patch-Z.mpq) bytes"
+          # Read the archive back with StormLib (mpqpack --list/--cat).
+          docker run --rm --entrypoint mpqpack -v "$PWD/test:/work" mpq-packager:ci \
+            --list /work/dist/patch-Z.mpq | tee /tmp/list.txt
+          grep -q 'Interface\\AddOns\\Fixture\\Hello.lua' /tmp/list.txt
+          docker run --rm --entrypoint mpqpack -v "$PWD/test:/work" mpq-packager:ci \
+            --cat /work/dist/patch-Z.mpq 'Interface\AddOns\Fixture\Hello.lua' \
+            | grep -q 'VERSION = "v0.0.0-ci"'
+          echo "OK: archive valid, path + substitution confirmed"