fix(git): review follow-ups for #1357 (S1, S2, indent)

S1: get_gitea_login_for_repo_override() now distinguishes "tea is not
installed" from "no tea login named X exists", mirroring the host path.
The old message diagnosed a cause that was never checked and pointed at
seat-logins.sh, which cannot run without tea. Branch 6 in
test-gitea-login-resolution.sh pins it (tea removed from PATH); reverting
the fix fails that branch.

S2: issue-list/pr-list/pr-view override-path error now points at the
lines above for the cause instead of suggesting a default tea login.

verify-release.mjs: indent of the #1356 test line fixed (cosmetic).

packages/mosaic/framework/tools/git/pr-list.sh

@@ -95,7 +95,7 @@ case "$PLATFORM" in
     gitea)
         if [[ -n "$REPO_OVERRIDE" ]]; then
             GITEA_LOGIN_NAME=$(get_gitea_login_for_repo_override "$REPO_OVERRIDE") || {
-                echo "Error: Could not resolve Gitea login for --repo override. Set GITEA_LOGIN or configure a default tea login." >&2
+                echo "Error: could not resolve a Gitea login for the --repo override (the lines above say why). Set GITEA_LOGIN to name one explicitly." >&2
                 exit 1
             }
         else