dbt_lineage: misleading hints for a column or an unknown model #1668

Found during the v0.12.9 release review (#1647).

• With column on the manifest path, a real column and a typo get the same note (tracing nope needs the dbt integration) and the whole model's lineage at high confidence. Nothing says the column doesn't exist, or that the integration only runs with --allow-write.
• "Run dbt compile first" is printed for an unknown model and for a corrupt manifest, where it's the wrong advice. impact_analysis lists the available models; dbt_lineage doesn't.
• include_graph changes nothing in plain-text output; the graph is only in --json.
• The analyst and data-explorer aren't read-only for dbt_lineage: they can start the adapter (dbt deps, target/ writes), as sql_execute already can.