Fix plugin script path resolution (#535)

Makes plugin instructions execute the installed plugin copy, safely quotes paths containing spaces, removes the broad Node pre-approval, and ships guarded generated plugin output.\n\nAI-assisted maintainer conflict resolution, review, and validation by Codex under maintainer direction.

scripts/test-suites.mjs

@@ -46,6 +46,7 @@ export const SUITES = {
           'tests/skills-cli.test.js',
           'tests/validate-plugin-versions.test.js',
           'tests/validate-plugin-manifest.test.js',
+          'tests/plugin-paths.test.js',
         ],
       },
       {
@@ -233,6 +234,7 @@ export const SUITES = {
       /^skill\/agents\//,
       /^scripts\/build\.js$/,
       /^scripts\/lib\/validate-plugin-manifest\.js$/,
+      /^scripts\/lib\/plugin-paths\.js$/,
       /^tests\/plugin-e2e\.test\.mjs$/,
     ],
     commands: [