fix(editor): solid-filled connected port + larger dot + tooltip fallback

Three issues from Stefan's screenshot:

1. Connected port dots rendered as a ring with a small
   surface-coloured pin in the centre — read as a hollow
   bullseye target rather than 'this port is wired'.
   Stefan asked for a plain filled circle: removed the
   inner pin so connected = solid disc, disconnected =
   ring with surface fill. One unambiguous visual switch.

2. Port dots bumped from 12 px to 14 px diameter. At 50 %
   zoom (and under the wider cards we now draw) the 12 px
   outline was sinking into the canvas background.

3. Tooltips now appear on every visible port label, not
   only on those whose ModuleSpec carries a description.
   Fallback chain:
     - manifest description in active locale
     - manifest description in English (peer)
     - 'fieldname · type' when the field is declared but
       the description is missing
     - bare 'fieldname' for implicit (YAML-only) fields
   Operators always see something on hover, useful when
   the hub binary is older than the per-field ModuleInfo
   RPC and the editor is running in implicit-only mode.

Bumps fai_studio_flow_editor to 0.10.3.

Signed-off-by: flemming-it <sf@flemming.it>

pubspec.yaml

@@ -1,6 +1,6 @@
 name: fai_studio_flow_editor
 description: Swappable inline YAML editor for F∆I Studio flows.
-version: 0.10.2
+version: 0.10.3
 publish_to: 'none'
 repository: https://git.flemming.ai/fai/studio-flow-editor