_style_anchor finds no exemplars in any repo not laid out as a src/ package

[lorenzoliuzzo]

Found while running my-coder for real against an external target repo (a flat-layout Python project: model.py, main.py at the root, no src/).

_style_anchor filters candidate exemplars to paths under src/ or tests/ (coder.py:225):

exemplars = sorted(
    (p for p in listed if p.endswith(".py") and (p.startswith(("src/", "tests/")))),
    ...
)

Every fleet repo is scaffolded from my-template and so has src/, which is why this has never shown. Any other repo gets either the literal fallback

Existing code: (none yet — this is an early/greenfield repo).

on a repo full of code, or — as measured here — a single trivial file.

Measured, dumping the real prompt for an issue about model.py: the sole "representative existing file" was a 7-line tests/test_model.py. model.py — the file the issue is about, and the largest module in the repo — was not shown, while my-searcher had correctly ranked it first. The prompt then instructs the session to "match the conventions of the existing code shown above", so it matches a 7-line test.

Acceptance criteria

• Exemplar selection is layout-agnostic: a flat-layout repo yields its real modules.
• Directories that are noise rather than house style stay excluded (vendored code, generated files, the existing .venv/__pycache__ exclusions).
• A test covering a flat-layout repo (no src/) that asserts a root-level module is picked as an exemplar.
• The existing src/-layout behaviour is unchanged.