feat: salvage mysql patterns skill (#1733)

- add a maintainer-reviewed MySQL/MariaDB production patterns skill based on PR #1727

- register the skill in database install module and npm publish allowlist

- sync catalog counts to 53 agents, 200 skills, and 69 commands

package.json

@@ -186,6 +186,7 @@
     "skills/market-research/",
     "skills/mcp-server-patterns/",
     "skills/messages-ops/",
+    "skills/mysql-patterns/",
     "skills/nanoclaw-repl/",
     "skills/nestjs-patterns/",
     "skills/netmiko-ssh-automation/",