Issue #20: bump MAX_BOTTOM_HANDLES 48 -> 64 (covers 48+4 SFP switches) and add
a per-node "Show Port Numbers" toggle that labels each bottom connection point.
Issue #21: add `fibre` as a first-class edge/connection type (bright cyan with a
subtle glow) alongside ethernet/wifi/iot/vlan/virtual/cluster - selectable in the
edge modal, themeable, registered in the React Flow edgeTypes registry, and
round-tripped through YAML import/export.
Backport of homelable-hacs PR #23.
ha-relevant: yes
Replaces the 4-option dropdown with a 1..48 slider. Existing handle IDs
('bottom', 'bottom-2'..'bottom-4') are preserved and the hand-tuned pixel
positions for counts 1..4 are locked in (regression-tested) so saved
canvases render identically. Counts >=5 use uniform spacing; node card
auto-grows in width so handles stay clickable. Existing edge-remap on
shrink scales unchanged thanks to its index-based loop.
ha-relevant: yes