feat: add Debian package building to CI pipeline and local build

Support DEB packaging alongside RPM for Debian trixie (13/stable),
forky (14/testing), Ubuntu noble (24.04 LTS), and plucky (25.04).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -21,6 +21,8 @@
     "completions:check": "tsx scripts/generate-completions.ts --check",
     "rpm:build": "bash scripts/build-rpm.sh",
     "rpm:publish": "bash scripts/publish-rpm.sh",
+    "deb:build": "bash scripts/build-deb.sh",
+    "deb:publish": "bash scripts/publish-deb.sh",
     "release": "bash scripts/release.sh",
     "mcpd:build": "bash scripts/build-mcpd.sh",
     "mcpd:deploy": "bash deploy.sh",