chore(sequencer-relayer)!: minimize resubmissions to Celestia

[Fraser999]

Summary

The relayer has been updated to avoid resubmitting the same data to Celestia on restart or on a timeout of the BroadcastTx gRPC.

Background

Currently the relayer will likely resubmit the same data when it restarts, since the majority of the time spent in the submit loop is waiting for confirmation of the BlobTx having been stored. While in this state, the on-disk files aren't updated to indicate that we're waiting for confirmation. Hence if we restart, the new session begins by submitting all data from the last-confirmed point, i.e. the same data which was already likely successfully submitted in the final attempt of the previous session.

A similar situation happens if we timeout while waiting for the BroadcastTx response - the retry loop will attempt to resubmit the same data without first checking if the previous attempt succeeded.

Changes

• Replaced the two state files (presubmit and postsubmit) with a single one (submission-state) and similarly for their respective env vars. See the updated spec for further details.
• The submission module was heavily changed: there are now two primary state structs StartedSubmission and PreparedSubmission, between which the blob submitter toggles during normal operation. There is also FreshSubmission which is only relevant at startup, and an enum covering these three (SubmissionStateAtStartup) which is also only used during startup. Finally, the State enum is an ephemeral object only used to read/write the relevant state from/to disk.
• BlobSubmitter::run was modified to try to confirm the last submission attempt from the previous session if the state file indicated the relayer exited while in prepared state. If that submission is confirmed (the most likely outcome), then the sequencer blocks in that submission are simply skipped in the write loop. (We could try to avoid even fetching these sequencer blocks, but that would be a significantly more pervasive change, and is probably not worth the complexity).
• The relayer's celestia client was changed to split try_submit into try_prepare and try_submit so that the hash of the prepared BlobTx can be returned from try_prepare to be recorded in the state file before the transaction is broadcast to the Celestia app.
• submit_with_retry was updated to check for a broadcast timeout error in the previous attempt, and in that case, attempts to just confirm that submission rather than automatically resubmitting the same data.

Testing

• Unit tests for the new submission types.
• Black box test later_height_in_state_leads_to_expected_relay was updated.
• Manually observed expected behaviour against a locally-running sequencer and Celestia app.

Breaking Changelist

• Removed ASTRIA_SEQUENCER_RELAYER_PRE_SUBMIT_PATH and ASTRIA_SEQUENCER_RELAYER_POST_SUBMIT_PATH config env vars.
• Added ASTRIA_SEQUENCER_RELAYER_SUBMISSION_STATE_PATH config env var.

Related Issues

Closes #1200.

[SuperFluffy]

This looks great and I don't see any outright blockers, just a bunch of requests for stylistic changes and tightening naming (to make the use of types and states clearer on a first read).

A big request I have is to not omit the use of context in error handling. While an author might have reason to avoid the context (for example, because ample information is provided in the called function), it's not at all clear for a reviewer. :)

[quasystaty1]

LGTM, tested locally