feat: new token emission

[gsk967]

Description

closes: #XXXX

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Author Checklist

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[codecov]

Codecov Report

Merging #2145 (3cbf87e) into main (7f05ad4) will decrease coverage by 5.16%.
Report is 150 commits behind head on main.
The diff coverage is 80.77%.

@@            Coverage Diff             @@
##             main    #2145      +/-   ##
==========================================
- Coverage   75.38%   70.23%   -5.16%     
==========================================
  Files         100      148      +48     
  Lines        8025    11319    +3294     
==========================================
+ Hits         6050     7950    +1900     
- Misses       1589     2824    +1235     
- Partials      386      545     +159     

Files Changed	Coverage Δ
ante/spam_prevention.go	75.92% <ø> (ø)
x/incentive/codec.go	47.82% <ø> (+9.89%)	⬆️
x/incentive/keeper/invariants.go	0.00% <0.00%> (ø)
x/incentive/keeper/unbonding.go	80.45% <ø> (ø)
x/incentive/keeper/update.go	52.11% <ø> (ø)
x/incentive/keys.go	100.00% <ø> (ø)
x/incentive/msgs.go	77.41% <ø> (-0.81%)	⬇️
x/incentive/params.go	89.28% <ø> (-10.72%)	⬇️
x/leverage/client/tests/suite.go	100.00% <ø> (ø)
x/leverage/client/tests/tests.go	100.00% <ø> (ø)
... and 54 more

... and 54 files with indirect coverage changes

[robert-zaremba]

let's consider using basis points for efficiency.
in proto it will be

  uint32 inflation_reduction_rate = 3 [(gogoproto.customtype) = "github.com/umee-network/umee/util/bpmath.FixedBP"  ];

Will review the x/mint logic later

[robert-zaremba]

• Add changelog
• [ ]

[robert-zaremba]

for time storage, let's use store.SetTimeMs

[robert-zaremba]

partial review

[robert-zaremba]

almost there , few tiny improvements

[robert-zaremba]

LGTM