A C# method called through a static factory or fluent chain —
`Foo.Create().Bar()`, `JObject.Parse(s).Property(...)`,
`Instant.FromUtc(...).InZone(zone)` — lost the receiver's type, so the chained
method didn't resolve and the call was invisible to callers/impact/trace. Ports
the #645/#608 mechanism to C# (additive, like Java #751):
- Part 1: capture C# return types in the extractor, reading the `returns` field
(`static Foo Create()` -> `Foo`); predefined/array/generic/nullable/namespaced
types are normalized or skipped.
- Part 2: encode a chained `member_access_expression` receiver
(`Foo.Create(args).Bar()`) as `inner().Bar` with normalized empty parens, so
factory calls that take arguments still split. Non-chained member calls keep
their existing `recv.Method` text.
- Part 3: resolve via the shared matchDottedCallChain (now Java/Kotlin/C#),
validated by resolveMethodOnType so a wrong inference yields NO edge.
Known limitation (safe): C# extension-method chains don't resolve, since the
method lives on the extension class, not the receiver's type — no edge, never a
wrong one.
Validated: synthetic decoy + args + absent-method safety tests; full suite green;
real-repo A/B on Newtonsoft.Json (945 .cs: +3, 0 lost) and nodatime (488 .cs:
+73, 0 lost) — node count identical (no explosion), 0 edges lost, precision
spot-checked verbatim (Instant.FromUtc().InZone(), Offset.FromHoursAndMinutes().Plus(),
OffsetDateTimePattern.CreateWithInvariantCulture().WithTwoDigitYearMax()).
EXTRACTION_VERSION 7 -> 8.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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