Seven correctness and documentation fixes found in the final review:
- `known_sources()`: check the strtol end pointer and add a round-trip
guard so a filename that layout_path() could not have produced is
rejected; without it `foo_8000x.toml` listed as `foo:8000` whose `x`
would unlink `foo_8000.toml`, a different configured session.
- `chooser_finish()`: destroy the form window before the chooser window;
a row click or Escape while the form was up left a window whose handlers
pointed at a dead stack frame (latent use-after-free).
- `choose_source()`: keep the pick_probe timeout id and g_source_remove
it after the loop; a row picked before the delay elapsed left an armed
source on the main context pointing at the gone frame.
- `chooser_populate()`: replace a false comment ("not a GtkListBoxRow")
with the truth — GTK4 auto-wraps, but the wrapped row carries no
source-index data so the bounds check refuses it.
- `pick_probe()`: collapse the duplicate `known.empty()` / `row==nullptr`
guards; the second was unreachable and two identical lines for one cause
makes probe output ambiguous.
- `save_layout()`: state the TOML rule directly in the multicast/interface
comment rather than cross-referencing the adjacent enabled comment.
- `save_layout_now()`: refuse to write when signals() is empty; a run
against a dead port receives no CONFIG, so every slot name is empty and
the save would overwrite a configured session with signals=["",...],
which the chooser filter refuses, silently removing that source from
the only list it can be picked from.
- Fix include order in layout_store.cpp (<cstdio> before <cstdlib>).
- Update CLAUDE.md and README.md to document the empty-signals guard and
fix the probe-output quote to match the emitted text exactly.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
