fix: DMQ publisher error on rejected local submission response

[jpraynaud]

Content

This PR includes a fix to:

• Abort the Pallas DMQ client upon reception of an error (to avoid long lived connections to the DMQ server which could fail)
• Support the update of the Pallas library that fixes the CBOR encoding for rejected messages in local submission mini-protocol

Pre-submit checklist

• Branch
  • Tests are provided (if possible)
  • Crates versions are updated (if relevant)
  • Commit sequence broadly makes sense
  • Key commits have useful messages
• PR
  • All check jobs of the CI have succeeded
  • Self-reviewed the diff
  • Useful pull request description
  • Reviewer requested

Issue(s)

Relates to #2961

[Copilot]

Pull request overview

Fixes DMQ publisher connection handling and aligns DMQ rejection encoding with an updated Pallas API to prevent long-lived connections when local submission responses are rejected.

Changes:

• Update DMQ server rejected-response construction to use DmqMsgRejectReason (new Pallas API).
• Adjust DMQ publisher client flow around receiving the submit response and sending Done.
• Switch pallas-* dependencies to a git branch to pick up the CBOR-encoding fix.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 3 comments.

File	Description
internal/mithril-dmq/src/publisher/server/pallas.rs	Updates rejected response payload to the new DmqMsgRejectReason-based structure.
internal/mithril-dmq/src/publisher/client/pallas.rs	Refactors response handling / graceful termination logic and updates tests for new reject reason type.
internal/mithril-dmq/Cargo.toml	Switches pallas-codec / pallas-network from crates.io to a git branch dependency.
Cargo.lock	Locks new git-sourced Pallas versions and their transitive dependency changes.

---

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[Copilot]

pallas-codec / pallas-network are switched to a moving git branch dependency. This makes builds non-reproducible over time (branch can change) and bypasses crates.io versioning; it also complicates supply-chain auditing. Prefer pinning to an immutable rev (commit) or a released/tagged version, or use a [patch.crates-io] override at the workspace level if this is a temporary hotfix. Also consider removing the commented-out dependency lines to avoid configuration drift.

Suggested change

	#pallas-codec = { version = "0.34.0" }
	#pallas-network = { version = "0.34.0" }
	pallas-codec = { git = "https://github.com/cardano-scaling/pallas.git", branch = "jpraynaud/fix-dmq-local-submission" }
	pallas-network = { git = "https://github.com/cardano-scaling/pallas.git", branch = "jpraynaud/fix-dmq-local-submission" }
	pallas-codec = { git = "https://github.com/cardano-scaling/pallas.git", rev = "0123456789abcdef0123456789abcdef01234567" }
	pallas-network = { git = "https://github.com/cardano-scaling/pallas.git", rev = "0123456789abcdef0123456789abcdef01234567" }

[github-actions]

Test Results

    5 files  ±0    172 suites  ±0   33m 19s ⏱️ +28s
2 452 tests ±0  2 452 ✅ ±0  0 💤 ±0  0 ❌ ±0 
7 654 runs  ±0  7 654 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit e61573f. ± Comparison against base commit 2f5a13f.

[turmelclem]

LGTM 👍