Adds repl_build_prompt(), building the readline() prompt fresh each
loop iteration: the plain "(sim) " before any session begins, else
"(sim session=<N> t=<ISO8601-ts>) " using the bare session count (not
+1, matching info session's convention) and the existing
repl_format_ts_human(). Both of task 6.1's tests pass.
repl.c grew 808->852 lines (6.5% over the 800-line cap). Review
empirically tried extracting repl_build_prompt() into a new
repl_prompt.c: it works, but requires updating 19 sibling white-box
test files' #include lists, and even then repl.c only drops to 814
lines - still over cap. Given the function is a small 15-line
formatter and the split doesn't even achieve compliance, accepted in
place rather than forcing disproportionate churn.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YAWMhfRJFnmmnG8h97yUDd
Rongsong Shen
da6ba96eb4