feat(marketplace): add domain metadata to all plugins [BREAKING]

- domain field required in plugin.json and marketplace.json (core/data/ops)
- validate-marketplace.sh enforces domain presence and allowed values
- claude-launch.sh new profiles: saas, ops, debug; infra deprecated
- CANONICAL-PATHS.md and CLAUDE.md updated with domain conventions

BREAKING CHANGE: validate-marketplace.sh rejects plugins without domain field

Version: 8.0.0

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

plugins/doc-guardian/.claude-plugin/plugin.json

@@ -9,6 +9,15 @@
   "homepage": "https://gitea.hotserv.cloud/personal-projects/leo-claude-mktplace/src/branch/main/plugins/doc-guardian/README.md",
   "repository": "https://gitea.hotserv.cloud/personal-projects/leo-claude-mktplace.git",
   "license": "MIT",
-  "keywords": ["documentation", "sync", "drift-detection", "automation", "hooks"],
-  "commands": ["./commands/"]
+  "keywords": [
+    "documentation",
+    "sync",
+    "drift-detection",
+    "automation",
+    "hooks"
+  ],
+  "commands": [
+    "./commands/"
+  ],
+  "domain": "core"
 }