fix(genReport): prevent KeyError when no .log files by initializing last_log

[ashnaaseth2325-oss]

1. SUMMARY

This PR fixes a crash in genReport.py caused by accessing an uninitialized last_log key when no .log files are present. It ensures safe initialization and consistent behavior with existing fields.

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2. FIX

# Before
d["log_errors"] = list()
d["log_warnings"] = list()
for name_ in sorted(files):
    if name_.endswith(".log"):
        d["last_log"] = name_
d["finished"] = d["last_log"] in LAST_EXPECTED_LOG

# After
d["log_errors"] = list()
d["log_warnings"] = list()
d["last_log"] = ""
for name_ in sorted(files):
    if name_.endswith(".log"):
        d["last_log"] = name_
d["finished"] = d["last_log"] in LAST_EXPECTED_LOG

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3. VERIFICATION

Tested by running genReport.py on a log directory with no .log files and with only non-log files present. The script no longer crashes and completes execution without any traceback. The report is generated correctly with finished=False, confirming graceful handling of missing logs.

[ashnaaseth2325-oss]

Hi @maliberty @eder-matheus,
Kindly review this PR.
Thanks!