fix: Bump stale compat floors for EvoTrees, OffsetArrays, StatsBase

[sethaxen]

Summary

The Downgrade CI job (Julia min) has been failing on main with ERROR: LoadError: Unsatisfiable during the merged-resolution step. Reproduced locally with Pkg.resolve() (not just Resolver.jl's terse error) and traced it to three genuinely-unreachable compat floors, all confirmed against the General registry:

• StatsBase = "0.33.7, 0.34" → "0.33.17, 0.34": PosteriorStats (weakdep, floor 0.3) requires StatsBase 0.33.17-0.34 starting at PosteriorStats v0.3.0, so our claimed 0.33.7 floor was never actually reachable alongside our own PosteriorStats floor.
• OffsetArrays = "1" → "1.0.1": resolves to exactly 1.0.0, but Interpolations (pulled in transitively via PosteriorStats → KernelDensity → Interpolations) explicitly excludes 1.0.0 (compat: [0.10-0.11, 1.0.1-1]).
• EvoTrees = "0.16" → "0.16.3": resolves to 0.16.0, where CUDA was still a hard dependency (not a weakdep), and that CUDA version's GPUCompiler requirement doesn't support Julia 1.10 (our julia floor). CUDA became a weakdep of EvoTrees starting at v0.16.3.

Since StatsBase is a weakdep (triggers InferenceObjectsPosteriorStatsExt) and its compat floor changed, this also bumps the patch version per repo convention.

Verification

• Pkg.resolve() on the merged (extras-promoted) project now succeeds on Julia 1.10, where it previously errored with Unsatisfiable.
• With [compat] pinned to the new floor versions on the real Project.toml (weakdeps/extensions intact), Pkg.test() passes cleanly: 2085 passed, 21 broken (pre-existing), 0 failed, 0 errored. All three packages resolve at exactly their new floors, and all three extensions (NCDatasets, MCMCDiagnosticTools, PosteriorStats) load correctly.
• Normal Pkg.resolve() at latest versions still succeeds (only lower bounds changed).

Test plan

• CI passes, in particular the Downgrade / Julia min - ubuntu-latest job

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.16%. Comparing base (6eb1418) to head (a915414).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #122      +/-   ##
==========================================
+ Coverage   91.58%   92.16%   +0.57%     
==========================================
  Files          24       24              
  Lines         535      536       +1     
==========================================
+ Hits          490      494       +4     
+ Misses         45       42       -3     

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