Add emergency-para-xcm to Moonbase

[elfedy]

What does it do?

Adds emergency-para-xcm pallet to Moonbase

Is there something left for follow-up PRs?

This pallet needs to be tested properly with a flow that:

1. Simulates a parachain "halt" that triggers paused xcm mode.
2. Verifies we enter the mode and that xcm messages from both hrmp and dmp are enqueued but not processed.
3. Bring the chain back to "normal" mode and resume operations.

Are there relevant PRs or issues in other repositories (Substrate, Polkadot, Frontier, Cumulus)?

Moonsong-Labs/moonkit#34
Moonsong-Labs/moonkit#38

What value does it bring to the blockchain users?

This chains aims to mitigate the risk of a particular xcm halting the chain due to taking a long time to process or generating a big PoV.

[github-actions]

Coverage Report

@@                    Coverage Diff                    @@
##           master   elfedy-auto-pause-xcm      +/-   ##
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+ Coverage   72.46%                  72.47%   +0.01%     
  Files         229                     229              
- Lines       70512                   70501      -11     
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  Hits        51094                   51094              
- Misses      19418                   19407      -11     

Files Changed	Coverage

Coverage generated Wed Apr 10 15:00:17 UTC 2024

[librelois]

Added to moonriver and moonbeam in #2913