feat: implement convenient path methods + add iteration key

[Farhad-Shabani]

Closes: #1090
Closes: #1089

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PR author checklist:

• Added changelog entry, using unclog.
• 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: 76 lines in your changes are missing coverage. Please review.

Comparison is base (3b260e2) 66.81% compared to head (a5f0536) 66.58%.

Files	Patch %	Lines
ibc-core/ics24-host/types/src/path.rs	26.80%	71 Missing ⚠️
ibc-query/src/core/connection/query.rs	0.00%	2 Missing ⚠️
ibc-clients/ics07-tendermint/src/client_state.rs	75.00%	1 Missing ⚠️
ibc-query/src/core/channel/query.rs	0.00%	1 Missing ⚠️
ibc-query/src/core/client/query.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1091      +/-   ##
==========================================
- Coverage   66.81%   66.58%   -0.23%     
==========================================
  Files         204      204              
  Lines       20437    20519      +82     
==========================================
+ Hits        13654    13663       +9     
- Misses       6783     6856      +73     

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