[bewaterhere-coder]

Summary

• Activate professional guidance from valid, explicitly selected Profile plugins, not from automatic discovery results.
• Keep discovery limited to candidate suggestions and preview-only advisory output.
• Add a regression test where Unity is explicitly selected and Unity source exists, but the normal Unity discovery marker is absent.
• Update the Chinese and English README and best-practices guide.

Why

The Core previously built professional_guidance by filtering discovered plugins against the selected set. An explicitly selected plugin therefore produced no professional guidance when its detection marker was absent. This conflated discovery with activation and made an explicit Profile selection ineffective for source-only or nonstandard project layouts.

Expected behavior

• Discovery suggests plugins; it does not activate them.
• Explicit Profile selection activates that plugin's professional guidance independently of detection markers.
• If no matching source evidence is found, the result remains not_evaluated.
• Unselected plugins remain inactive.
• All findings remain advisory and non-blocking.

Scope

Core selection semantics, regression test and bilingual documentation only. No plugin manifests or public API changes.

Validation

GitHub Actions: Python 3.10–3.13, MCP stdio E2E and Sample Project Advisory.