Resolves the two Codex P2s raised on #4420 that merged unaddressed:
- wrapUrlRows indented every continuation chunk. A multi-row terminal
selection includes the newline plus that indent; address bars strip
newlines but preserve or percent-encode embedded spaces, so the
reassembled URL was corrupted at every chunk boundary - silently,
when the damage landed inside a query value. Chunk rows now carry
zero leading bytes (label rows keep their indent), and the test
reassembly helper concatenates chunks raw instead of stripping the
indent that previously masked exactly this defect.
- #launchUrlIfSafe advertised a localhost /launch copy target for
flows whose redirectUri never returns to the loopback server. Its
catch-comment assumed custom-scheme URIs are non-parseable, but
new URL('vscode://gitlab.gitlab-workflow/authentication') parses
fine and sailed through the pathname check. The guard now requires
an http(s) loopback redirectUri (localhost / 127.0.0.1 / [::1]);
custom schemes, non-loopback hosts, and unparseable URIs all
suppress the launch URL. Regression tests cover the GitLab Duo
vscode:// shape and a fixed non-loopback HTTPS redirect.
Refs #4418