feat(app): set up post handler for tx tips

[technicallyty]

Description

enables tx tips on the application

Closes: #1331

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[codecov[bot]]

Codecov Report

Merging #1454 (90b279a) into main (4ef8001) will decrease coverage by 0.00%. The diff coverage is 75.00%.

@@            Coverage Diff             @@
##             main    #1454      +/-   ##
==========================================
- Coverage   78.48%   78.47%   -0.01%     
==========================================
  Files         238      238              
  Lines       18439    18447       +8     
==========================================
+ Hits        14471    14477       +6     
- Misses       3126     3127       +1     
- Partials      842      843       +1     

Impacted Files	Coverage Δ
app/stable_appconfig.go	44.18% <71.42%> (+5.29%)	:arrow_up:
app/app.go	92.70% <100.00%> (+0.01%)	:arrow_up:

[ryanchristo]

Would be great if you could do a little research on how we might use transaction tips before we implement this.

[technicallyty]

Would be great if you could do a little research on how we might use transaction tips before we implement this.

• user receives ecocredits from send/create_batch/bridge but has no REGEN balance, can then move the credits around w/o having to acquire REGEN (keep in mind, REGEN will still cycle through the system, its just paid for by the fee payer/relayer in exchange for whatever the user's tip is)
• the ol' "staked all my coins but now i can't claim my rewards" problem can be fixed w/ tips 😺
• validator w/ extra liquid REGEN can setup a market for tips allowing them to earn other IBC coins for regen ledger transactions

also fair warning, we may want to keep this blocked for now as it is technically still beta software. may want to consider waiting till full release

[ryanchristo]

On hold until we have automated fee payer infrastructure in place. Until then, using the tips field will error rather than no error with no automated fee payer infrastructure in place.

[ryanchristo]

Closing this as we are not planning to implement a fee payer infrastructure and we are considering an alternative (allowing for multiple fees - another solution that chains are using). We can re-open and revisit if we change our mind.