Fix false-positive validation timeouts

[georgeee]

Fix validation timeout for duplicate blocks from same block producer

Fire validation callback with Ignore when blocks are already in frontier
or in process, preventing misleading "Validation timed out" errors when
multiple nodes use the same block producer key.

Explain how you tested your changes:

• Test on the cluster

Checklist:

• Dependency versions are unchanged
  • Notify Velocity team if dependencies must change in CI
• Modified the current draft of release notes with details on what is completed or incomplete within this project
• Document code purpose, how to use it
  • Mention expected invariants, implicit constraints
• Tests were added for the new behavior
  • Document test purpose, significance of failures
  • Test names should reflect their purpose
• All tests pass (CI will check this if you didn't)
• Serialized types are in stable-versioned modules
• Does this close issues? None

[dkijania]

!ci-docker-me

[dkijania]

File "src/lib/transition_frontier_controller/transition_frontier_controller.ml", line 128, characters 50-73:
128 |     ~transition_reader:network_transition_reader ~valid_transition_writer
                                                        ^^^^^^^^^^^^^^^^^^^^^^^
Error: This expression has type
         ([ `Block of
              (Transition_handler.Unprocessed_transition_cache.Transmuter.Source.t,
               Pasta_bindings.Fp.t)
              Cache_lib.Cached.t
          | `Header of
              ('a, 'b, 'c, 'd, 'e, 'f, 'g) Validation.with_header
              Network_peer.Envelope.Incoming.t ] *
          [< `Valid_cb of Mina_net2.Validation_callback.t option ],
          Strict_pipe.drop_head Strict_pipe.buffered, unit)
         Strict_pipe.Writer.t
       but an expression was expected of type
         ([ `Block of
              (Transition_handler.Unprocessed_transition_cache.Transmuter.Source.t,
               Pasta_bindings.Fp.t)
              Cache_lib.Cached.t
          | `Header of
              ('a, 'b, 'c, 'd, 'e, 'f, 'g) Validation.with_header
              Network_peer.Envelope.Incoming.t ] *
          [> `Valid_cb of Mina_net2.Validation_callback.t ], 'h, unit)
         Strict_pipe.Writer.t
       Types for tag `Valid_cb are incompatible
make: *** [Makefile:145: build] Error 1
🚨 Error: The command exited with status 2

unfortunately it does not compile

[glyh]

!ci-docker-me

[glyh]

https://buildkite.com/o-1-labs-2/mina-build-docker/builds/190