Setup definitions and functions for Interchain Accounts application

[Farhad-Shabani]

Closes: #735

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PR author checklist:

• Added changelog entry, using unclog.
• Added tests.
• Linked to GitHub issue.
• Updated code comments and documentation (e.g., docs/).
• Tagged one reviewer who will be the one responsible for shepherding this PR.

Reviewer checklist:

• Reviewed Files changed in the GitHub PR explorer.
• Manually tested (in case integration/unit/mock tests are absent).

[codecov]

Codecov Report

Attention: Patch coverage is 6.20891% with 1284 lines in your changes are missing coverage. Please review.

Project coverage is 67.92%. Comparing base (dcf8c36) to head (16aef3a).

❗ Current head 16aef3a differs from pull request most recent head ee7b0be

Please upload reports for the commit ee7b0be to get more accurate results.

Files	Patch %	Lines
.../applications/interchain_accounts/host/callback.rs	0.00%	256 Missing ⚠️
...cations/interchain_accounts/controller/callback.rs	0.00%	202 Missing ⚠️
...c/src/applications/interchain_accounts/metadata.rs	0.00%	160 Missing ⚠️
...bc/src/applications/interchain_accounts/account.rs	0.00%	82 Missing ⚠️
.../ibc/src/applications/interchain_accounts/error.rs	0.00%	80 Missing ⚠️
.../controller/handler/register_interchain_account.rs	0.00%	69 Missing ⚠️
.../interchain_accounts/controller/handler/send_tx.rs	0.00%	64 Missing ⚠️
crates/ibc/src/core/msgs.rs	0.00%	53 Missing ⚠️
...interchain_accounts/host/handler/on_recv_packet.rs	0.00%	47 Missing ⚠️
...ibc/src/applications/interchain_accounts/packet.rs	0.00%	41 Missing ⚠️
... and 11 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #719      +/-   ##
==========================================
+ Coverage   65.56%   67.92%   +2.35%     
==========================================
  Files         234      139      -95     
  Lines       23519    17314    -6205     
==========================================
- Hits        15421    11761    -3660     
+ Misses       8098     5553    -2545     

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