feat: add package discovery recipes to justfile

Add three new recipes to CI/CD group for dynamic package discovery:
- list-packages: Lists all package names in packages/ directory
- list-packages-json: Outputs packages in JSON format for CI matrix usage
- validate-package: Checks that a package has valid structure

These recipes enable automated package discovery for CI workflows and
monorepo tooling without hardcoding package names.

Author: cameronraysmith

justfile

@@ -247,6 +247,33 @@ gh-cancel run_id="":
     gh run cancel {{run_id}} --repo $REPO
   fi
 
+# List all packages in packages/ directory
+[group('CI/CD')]
+list-packages:
+  @ls -1 packages/
+
+# List packages in JSON format for CI matrix
+[group('CI/CD')]
+list-packages-json:
+  #!/usr/bin/env bash
+  cd packages
+  packages=()
+  for dir in */; do
+    pkg_name="${dir%/}"
+    if [ -f "$dir/package.json" ]; then
+      packages+=("{\"name\":\"$pkg_name\",\"path\":\"packages/$pkg_name\"}")
+    fi
+  done
+  echo "[$(IFS=,; echo "${packages[*]}")]"
+
+# Validate package structure
+[group('CI/CD')]
+validate-package package:
+  @echo "Validating package: {{ package }}"
+  @test -d "packages/{{ package }}" || (echo "Package directory not found" && exit 1)
+  @test -f "packages/{{ package }}/package.json" || (echo "package.json not found" && exit 1)
+  @echo "✓ Package {{ package }} is valid"
+
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