Issues not returned by issue.filter (no access / deleted) and failures
of the time entry activities lookup were silently swallowed: the report
was built from partial data without telling the user.
Now both cases emit a warning to stderr (project ⚠️ style, #28):
- skipped issue IDs and total lost hours after issue matching;
- activities lookup failure (still returns {} and falls back to
activity names from time entries).
These are warnings, not errors: the report is still built from
available data and the exit code is unchanged.
Closes#61
594db90227