feat: monotonic sqrt big dec

[p0mvn]

Closes: #6045

What is the purpose of the change

To raise the minimum spot price in CL, we need to implement a MonotonicSqrt function on osmomath.BigDec to support higher precision.

See design document: https://app.clickup.com/37420681/v/dc/13nzm9-22453/13nzm9-45853

Testing and Verifying

Copied tests from regular MonotonicSqrt.

Benchmark

goos: linux
goarch: amd64
pkg: github.com/osmosis-labs/osmosis/osmomath
cpu: 12th Gen Intel(R) Core(TM) i7-1260P
                        │  reg.bench   │     big.bench      │
                        │    sec/op    │   sec/op     vs base   │
MonotonicSqrt-16          386.8µ ± 19%
MonotonicSqrt_BigDec-16                  470.0µ ± 2%
geomean                   386.8µ         470.0µ       ? ¹ ²
¹ benchmark set differs from baseline; geomeans may not be comparable
² ratios must be >0 to compute geomean

Documentation and Release Note

• Does this pull request introduce a new feature or user-facing behavior changes?
• Changelog entry added to Unreleased section of CHANGELOG.md?

Where is the change documented?

• Specification (x/{module}/README.md)
• Osmosis documentation site
• Code comments?
• N/A

[AlpinYukseloglu]

LGTM!