Two glitches visible in 0.15.1:
1. The flutter_code_editor gutter renders an Icons.cancel pin
for every analyzer issue, hard-positioned inside a 16-px
slot. With a single-digit indent the icon centres look off;
with double-digit line numbers it shifts further.
2. The hover popup for that pin paints at `offset.dx + width`
of the gutter cell — which lands INSIDE the code area, so
'Unknown capability ...' overlaps the YAML text the
operator is trying to read.
The package doesn't expose a fix for either — the icon is a
const in error.dart, the popup position is hard-coded in the
StatefulWidget. Cleanest path: hide the gutter error column
entirely (`GutterStyle.showErrors: false`) and surface the
analyzer issues through a dedicated bottom strip we own.
The new _DiagnosticStrip renders as a single 22-px line under
the editor: a coloured dot + 'N errors · M warnings · L7:
${first.message}'. Tap expands into a per-issue list capped at
140-px scroll, dot-coloured by IssueType. Empty state shows a
muted 'No issues' so the strip never disappears and never
shifts the layout.
Wavy underlines in the text body keep working untouched — the
two surfaces complement each other: the underline points at
the broken token, the strip names what's wrong.
Bumped to 0.16.0.
Signed-off-by: flemming-it <sf@flemming.it>