QA re-release: backend 1.1.27, frontend 1.1.70 (chat links)

Same version numbers, third set of frontend bits. Adds clickable links in chat
message bubbles — a URL rendered as plain text before, reachable only through
the preview card and only for the first link in a message.

  r1  sha256:5b90e224...
  r2  sha256:595d6257...  chevron menu height
  r3  sha256:3bbbc302...  chat links   <- deploy this one

The bundle is unchanged — same commit, same image tags — so this tag exists
only to keep the sets of bits distinguishable, per the re-release rule.

A target already reading 1.1.70 must 'docker compose pull frontend'; 'up -d'
alone will not fetch it. Verify by digest, not by tag.
This tag has no release notes.