fix(filings): match "purchases related to property" capex

Nvidia's cash-flow statement labels capex "purchases related to property
and equipment and intangible assets", which matched none of the five
existing stems. build_cashflow_context then returned None rather than
raising, so the caller's try/except logged nothing and capex/FCF vanished
from the newsletter's inside-ticker analysis with no trace.

Ordering is safe: the matcher takes the first row in document order per
key, and the "held"/"accrued" exclusions already cover the known decoys.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/TerraFin/interface/pages/stock/income_filing.py

@@ -270,7 +270,10 @@ _CF_LABELS = {
     # capex is worded several standard ways: "purchases of…", "expenditures for…"
     # (Micron, Intel), "additions to…", "payments to acquire…". Match on the stem
     # so the Oxford-comma / "plant and equipment" variants all resolve.
-    "capex": ("purchases of property", "expenditures for property", "additions to property",
+    # "purchases RELATED TO property" (Nvidia) matched none of the others, so the
+    # whole context returned None and the caller silently lost capex/FCF.
+    "capex": ("purchases of property", "purchases related to property",
+              "expenditures for property", "additions to property",
               "payments to acquire property", "capital expenditures"),
     "ocf": ("net cash provided by operating activities", "net cash from operating activities",
             "net cash generated by operating activities", "cash flows from operating activities"),