chore: release v0.21.0

[github-actions]

🤖 New release

• differential-dataflow: 0.20.0 -> 0.21.0 (⚠ API breaking changes)
• differential-dogs3: 0.20.0 -> 0.21.0 (✓ API compatible changes)

⚠ differential-dataflow breaking changes

--- failure constructible_struct_adds_field: externally-constructible struct adds field ---

Description:
A pub struct constructible with a struct literal has a new pub field. Existing struct literals must be updated to include the new field.
        ref: https://doc.rust-lang.org/reference/expressions/struct-expr.html
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/constructible_struct_adds_field.ron

Failed in:
  field DifferentialEventContainer.indexes in /tmp/.tmpOLyivv/differential-dataflow/differential-dataflow/src/logging.rs:26

--- failure function_missing: pub fn removed or renamed ---

Description:
A publicly-visible function cannot be imported by its prior path. A `pub use` may have been removed, or the function itself may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/function_missing.ron

Failed in:
  function differential_dataflow::algorithms::graphs::scc::trim, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/algorithms/graphs/scc.rs:16

--- failure module_missing: pub module removed or renamed ---

Description:
A publicly-visible module cannot be imported by its prior path. A `pub use` may have been removed, or the module may have been renamed, removed, or made non-public.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/module_missing.ron

Failed in:
  mod differential_dataflow::trace::implementations::merge_batcher::container::columnation, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:521
  mod differential_dataflow::trace::implementations::merge_batcher::container::vec, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:460

--- failure struct_missing: pub struct removed or renamed ---

Description:
A publicly-visible struct cannot be imported by its prior path. A `pub use` may have been removed, or the struct itself may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/struct_missing.ron

Failed in:
  struct differential_dataflow::trace::implementations::merge_batcher::container::ContainerMerger, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:297
  struct differential_dataflow::trace::implementations::chunker::VecChunker, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/chunker.rs:14
  struct differential_dataflow::trace::implementations::merge_batcher::container::columnation::TimelyStackQueue, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:535

--- failure struct_pub_field_missing: pub struct's pub field removed or renamed ---

Description:
A publicly-visible struct has at least one public field that is no longer available under its prior name. It may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/struct_pub_field_missing.ron

Failed in:
  field variant of struct DifferentialEventContainer, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/logging.rs:26
  field offset of struct DifferentialEventContainer, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/logging.rs:26

--- failure trait_missing: pub trait removed or renamed ---

Description:
A publicly-visible trait cannot be imported by its prior path. A `pub use` may have been removed, or the trait itself may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.46.0/src/lints/trait_missing.ron

Failed in:
  trait differential_dataflow::trace::implementations::merge_batcher::container::MergerChunk, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:259
  trait differential_dataflow::trace::implementations::merge_batcher::container::ContainerQueue, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/trace/implementations/merge_batcher.rs:247
  trait differential_dataflow::consolidation::ConsolidateLayout, previously in file /tmp/.tmpCoKlAr/differential-dataflow/src/consolidation.rs:241

Changelog

differential-dataflow

0.21.0 - 2026-03-25

Other

• Update to track timely 0.28 and columnar 0.12 (#698)
• Further columnar work (#697)
• Remove columnar::Stash-a-like (#696)
• Add Arranged::as_container convenience method (#695)
• Columnar tidy (#694)
• Migrate columnar example from chainless batcher to MergeBatcher (#693)
• Improve some graph algorithms (#692)
• Use more internal iteration (#689)
• Add columnation and columnar impls for Present (#682)

differential-dogs3

0.21.0 - 2026-03-25

Other

• update Cargo.toml dependencies

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This PR was generated with release-plz.