add Enzyme benchmarks and incorporate some CompatHelper bits

[penelopeysm]

Replaces #1039, #1053, #1054

[github-actions]

Benchmark Report for Commit 643dd12

Computer Information

Julia Version 1.11.7
Commit f2b3dbda30a (2025-09-08 12:10 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 4 × AMD EPYC 7763 64-Core Processor
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, znver3)
Threads: 1 default, 0 interactive, 1 GC (on 4 virtual cores)

Benchmark Results

┌───────────────────────┬───────┬─────────────┬───────────────────┬────────┬────────────────┬─────────────────┐
│                 Model │   Dim │  AD Backend │           VarInfo │ Linked │ t(eval)/t(ref) │ t(grad)/t(eval) │
├───────────────────────┼───────┼─────────────┼───────────────────┼────────┼────────────────┼─────────────────┤
│ Simple assume observe │     1 │ forwarddiff │             typed │  false │            8.8 │             1.6 │
│           Smorgasbord │   201 │ forwarddiff │             typed │  false │          778.8 │            39.9 │
│           Smorgasbord │   201 │ forwarddiff │ simple_namedtuple │   true │          429.4 │            57.3 │
│           Smorgasbord │   201 │ forwarddiff │           untyped │   true │         1221.6 │            31.1 │
│           Smorgasbord │   201 │ forwarddiff │       simple_dict │   true │         7581.7 │            25.2 │
│           Smorgasbord │   201 │ reversediff │             typed │   true │         1555.1 │            27.6 │
│           Smorgasbord │   201 │    mooncake │             typed │   true │         1091.2 │             4.3 │
│           Smorgasbord │   201 │      enzyme │             typed │   true │         1546.8 │             2.6 │
│    Loop univariate 1k │  1000 │    mooncake │             typed │   true │         5943.0 │             4.3 │
│       Multivariate 1k │  1000 │    mooncake │             typed │   true │         1061.0 │             8.7 │
│   Loop univariate 10k │ 10000 │    mooncake │             typed │   true │        66688.2 │             3.9 │
│      Multivariate 10k │ 10000 │    mooncake │             typed │   true │         9086.2 │             9.7 │
│               Dynamic │    10 │    mooncake │             typed │   true │          134.2 │            10.8 │
│              Submodel │     1 │    mooncake │             typed │   true │           13.0 │             5.0 │
│                   LDA │    12 │ reversediff │             typed │   true │         1085.3 │             2.0 │
└───────────────────────┴───────┴─────────────┴───────────────────┴────────┴────────────────┴─────────────────┘

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.39%. Comparing base (fcdfe03) to head (643dd12).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1056   +/-   ##
=======================================
  Coverage   82.39%   82.39%           
=======================================
  Files          39       39           
  Lines        3965     3965           
=======================================
  Hits         3267     3267           
  Misses        698      698           

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[coveralls]

Pull Request Test Coverage Report for Build 18006845176

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.646%

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Totals
Change from base Build 17982104071:	0.0%
Covered Lines:	3267
Relevant Lines:	3953

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💛 - Coveralls