tests: one front door

Fourteen test files, each its own __main__, and no way to run them but from
memory -- so in practice you ran the one you were working on and hoped. Worse,
nothing said which files need a licensed IDA and a real worker (minutes) and
which are pure stdlib (milliseconds), so the cheap ones nobody ran either.

tests/run.py runs the lot and prints one table. --fast selects only the suites
that need nothing, which is 257 checks in half a second under any python3 --
that's the one you run between edits.

The classification lives in the test files, not in a table here that would rot
the first time someone adds a test: each declares NEEDS_IDA at module scope and
run.py reads it with ast (it can't import them -- they run their suite at
import). A file without the marker is a hard error rather than a silent guess.

1 files changed, 4 insertions, 0 deletions

diff --git a/tests/test_graph.py b/tests/test_graph.py
index 9c0e792..146092d 100644
--- a/tests/test_graph.py
+++ b/tests/test_graph.py
@@ -11,6 +11,10 @@ monsters) actually live.
 """
 from __future__ import annotations
 
+#: the layout engine is pure: no IDA, no Textual.
+#: Read by tests/run.py (--fast skips every NEEDS_IDA file).
+NEEDS_IDA = False
+
 import json
 import os
 import sys