[zhongkechen]

The C# operation references omit released configuration fields, incremental parallel branches, custom subtype rules, and local checkpoint-token omission. Complete those references for Core 2.2.0 and Testing 1.1.0, and correct the documented handling of successful step results whose serialization or round-trip deserialization fails.

Scope

• Complete the operation-specific configuration signatures and parameter descriptions for steps, callbacks, child contexts, invokes, map, parallel, and polling.
• Document CreateParallel, typed branch handles, per-branch serializers, deterministic registration, and failed/skipped branch behavior. Add a separate incremental-branch example while retaining the existing named-branch example.
• Document custom subtype validation and replay stability for steps, callbacks, and child contexts.
• Document terminal StepException behavior for serialization and round-trip failures, including replay without repeating the successful step body.
• Document OmitCheckpointToken on the local TestRunnerOptions only.

Related PRs

• docs(csharp): document the per-operation serializer override (Step/Callback/Invoke/WaitForCondition/ChildContext + Map/Parallel ItemSerializer) #279 and docs(csharp): document the .NET FileSystem serializer (#2540) #280 own the per-operation serialization guide and filesystem serializer documentation/examples. Their commits, guide edits, and example edits are excluded from this PR. None of this PR's 13 changed files overlaps either PR.
• docs: refresh Java, TypeScript, and Python references #300 owns the shared prose and Java, TypeScript, and Python updates. All Markdown changes here are inside C# tabs.
• docs(python): correct 2.0 semantics in four pages #284 updates concurrency and Python semantics on some of the same operation pages, with different changes.

Merge checks against #279, #280, #284, and #300 each pass without conflicts.

Validation

• Zensical 0.0.40 clean build, full-site Markdown formatting/spelling, hidden-character checks, vendored-asset integrity checks, and git diff --check passed.
• All 688 example files are referenced. Local links and anchors passed across the nine changed rendered pages.
• Every retained file matches its previously validated content. The retained runnable C# examples compiled against Core 2.2.0 and Testing 1.1.0; focused runtime checks covered incremental branches and terminal serialization-failure replay. No SDK implementation changed.

Cloud integration and full cross-SDK conformance were not run. Browser visual preview was unavailable under the local-file URL policy; generated HTML was checked directly.