Spec sequence diagrams use light-theme SVGs on dark docs UI

[nficano]

Summary

Spec documentation embeds sequence diagram SVGs with -light.svg suffix on a dark docs background, producing low-contrast visuals.

Location(s)

• /spec/draft-arcp-1.1
• Breakpoints: 375, 1280

Severity

P2 — docs readability / polish

Evidence

CDP on /spec/draft-arcp-1.1:

{"imgs":[
  {"src":"http://localhost:3000/diagrams/spec/seq-heartbeat-liveness-light.svg","alt":"Heartbeat liveness sequence","ok":true},
  {"src":"http://localhost:3000/diagrams/spec/seq-event-ack-backpressure-light.svg","ok":true}
],"brokenImgs":0}

Docs UI renders dark while all spec diagrams use *-light.svg variants.

Suggested fix

Select diagram variant based on color mode or use theme-neutral SVGs.

Acceptance criteria

• Diagrams readable on current docs color scheme
• Dark-mode docs use dark diagram variants when available