fix(client/v2): improve message parsing by replacing proto.Merge with cloneMessage (backport #24722)

[mergify]

Description

Closes: ignite/cli#4623

@Pantani found an issue when using autocli but no pulsar module was present: ignite/cli#4623

• Pulsar shouldn't be mandatory, but proto.Merge fails when not present in modules (based on this SDK promise, Ignite v29 removed the pulsar file from its default template)
• The solution was to manually recursively merge the proto, avoiding the checks and assumptions proto.Merge does

We've checked the other usage of proto.Merge but they shouldn't matter.

cc @aaronc

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Author Checklist

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please add links to any relevant follow up issues. Your PR will not be merged unless you satisfy
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I have...

• included the correct type prefix in the PR title, you can find examples of the prefixes below:

• confirmed ! in the type prefix if API or client breaking change

• targeted the correct branch (see PR Targeting)

• provided a link to the relevant issue or specification

• reviewed "Files changed" and left comments if necessary

• included the necessary unit and integration tests

• added a changelog entry to CHANGELOG.md

• updated the relevant documentation or specification, including comments for documenting Go code

• confirmed all CI checks have passed

Summary by CodeRabbit

• Bug Fixes
  • Resolved an issue with message parsing when no pulsar file is present.

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This is an automatic backport of pull request #24722 done by [Mergify](https://mergify.com).

[ironbird-prod]

Ironbird - launch a network

To use Ironbird, you can use the following commands:

• /ironbird start OR /ironbird start --load-test-config= - Launch a testnet with the specified chain and load test configuration.
• /ironbird chains - List of chain images that ironbird can use to spin-up testnet
• /ironbird loadtests - List of load test modes that ironbird can run against testnet

Custom Load Test Configuration

You can provide a custom load test configuration using the `--load-test-config=` flag:

/ironbird start cosmos --load-test-config={
  "block_gas_limit_target": 0.75,
  "num_of_blocks": 50,
  "msgs": [
    {"weight": 0.3, "type": "MsgSend"},
    {"weight": 0.3, "type": "MsgMultiSend"},
	{"weight": 0.4, "type": "MsgArr", "ContainedType": "MsgSend", "NumMsgs": 3300}
  ]
}

Use /ironbird loadtests to see more examples.