تحلیل استک‌تریس و پیشنهاد ریشه

Explain this stack trace. Output exactly:

ROOT CAUSE: <one sentence — the most likely root cause>

EVIDENCE: <which frames support this and why>

THREE HYPOTHESES (ranked by likelihood):
  1. <hypothesis> → <one-line test to confirm or reject>
  2. <hypothesis> → <one-line test>
  3. <hypothesis> → <one-line test>

Skip generic advice. Stay specific to *this* trace.

Trace:
```
[paste stack trace]
```