_apply_filter parsed a name(arg) filter with an UNANCHORED regex
(re.match(r"(\w+)\((.+)\)")), so any tokens after the closing paren were
silently discarded. Because _evaluate_simple_expression splits the top-level
pipe before comparison/boolean operators, `count | default(0) > 5` was split
into value `count` and filter segment `default(0) > 5`; the segment matched
as `default(0)` and `> 5` vanished — the filter's value was returned as the
whole expression, giving a silently wrong result.
Use re.fullmatch so a mis-wired segment falls through to the existing
"unsupported form" ValueError, mirroring the from_json branch's strict
trailing-token handling. The greedy `.+` still matches legitimate forms
(literal `)` / `|` inside quoted args), so registered/chained/quoted-pipe
filters are unaffected.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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