Add feature to support mutation for array and map iterators

[fxamacker]

Closes #356 #357
Updates #292 onflow/flow-go#4633

Add support for mutable iterators, including support for atree splitting/merging during iteration from inlining, uninlining, and mutated values).

This feature was discussed on Discord:

• https://discord.com/channels/613813861610684416/1108479699732152503/1171188632359538778

Mutable iterator for array and map supports:

• indirect element mutation, such as modifying nested container
• direct element mutation, such as overwriting existing element with new element

Mutable iterator for array and map doesn't support:

• inserting new elements into the array/map
• removing existing elements from the array/map

NOTE: for better performance, use readonly iterator if mutation is not needed.

This PR:

• adds new interfaces ArrayIterator and MapIterator
• decouples implementation of mutable and readonly iterators
• refactors related functions

---

• Targeted PR against main branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[codecov-commenter]

Codecov Report

Attention: 175 lines in your changes are missing coverage. Please review.

Comparison is base (cb82995) 62.52% compared to head (5e67357) 62.45%.

Files	Patch %	Lines
map.go	61.06%	113 Missing and 33 partials ⚠️
array.go	67.04%	22 Missing and 7 partials ⚠️

Additional details and impacted files

@@                      Coverage Diff                       @@
##           feature/array-map-inlining     #359      +/-   ##
==============================================================
- Coverage                       62.52%   62.45%   -0.07%     
==============================================================
  Files                              15       15              
  Lines                           10599    10919     +320     
==============================================================
+ Hits                             6627     6820     +193     
- Misses                           3021     3119      +98     
- Partials                          951      980      +29     

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[ramtinms]

Looks good to me

[turbolent]

@fxamacker Do we still need this for onflow/cadence#2882?

[fxamacker]

Do we still need this for onflow/cadence#2882?

@turbolent Yes, we need this for integration PR.

[turbolent]

LGTM! I mainly reviewed it from a Go perspective, as in general, I lack a bit of understanding of the inner working of Atree to fully review if the changes are correct or if there is something missing