Count Copilot Findings Stated Only in a Review Notes File Table #3893

scripts/pr_review_copilot.py silently drops findings that a Copilot review states only in its file table, when the table's second column is headed Review notes.

Shape that is missed. A constructed example of the body shape:

<!-- ccr-overview-v2 -->
| File | Review notes |
|---|---|
| `scripts/example.py` | **[P1]** Guard the empty input before indexing it — moderate, 1 vote. |
| `scripts/other.py` | Reviewed. |

Why it is missed.

• The reader counts table findings only where a header cell equals the vocabulary's table_findings, which is "findings" in scripts/reviewers/copilot.json (pr_review_copilot.py around line 559).
• | File | Review notes | labels as ["file", "review notes"], so no table finding is counted.
• unthreaded = max(named - linked, 0) then reads 0 wherever every summary-list entry links a thread, so FINDINGS WITH NO THREAD never prints.
• placed() treats any table whose first header is file as placed, so no UNPLACED hold or note fires either.

The miss surfaced on #3892, where four table-only findings went uncounted and were answered by hand.

Care in the fix.

• Adding "review notes" to the vocabulary alone overcounts, since the tally counts any cell with alphanumeric text, and every Reviewed. row would read as a finding. Count on the [P\d] marker, or skip the filler text.
• One cell can hold two findings under one marker.
• A recognized table finding only adds to a count, so its text never prints under the block.
• No fixture in tests/test_pr_review_copilot.py has this header.

Done when a review carrying this shape prints its table-only findings under FINDINGS WITH NO THREAD with their text, and a Reviewed. row counts as nothing. A fixture of the shape above must pin it.