Update HISTORY.md for 0.42.0

[shravanngoswamii]

Adds a 0.42.0 entry to HISTORY.md covering #1363.

[github-actions]

DynamicPPL.jl documentation for PR #1408 is available at:
https://TuringLang.github.io/DynamicPPL.jl/previews/PR1408/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.58%. Comparing base (a115fa8) to head (4b7c9fb).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1408      +/-   ##
==========================================
- Coverage   81.70%   81.58%   -0.13%     
==========================================
  Files          50       50              
  Lines        3536     3578      +42     
==========================================
+ Hits         2889     2919      +30     
- Misses        647      659      +12     

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[github-actions]

Benchmarks @ 4b7c9fb

Performance Ratio: gradient time divided by log-density time.

For very small models these ratios are noisy across runs and machines; raw primal and gradient timings are more reliable. The benchmarks are aimed at DynamicPPL developers and mainly catch obvious allocation or type-stability regressions. See benchmark notes for details.

===================================================================================================
                                               eval                       gradient                 
                                            ----------  -------------------------------------------
Model                        dim    linked      primal     FwdDiff    RvsDiff    Mooncake    Enzyme
---------------------------------------------------------------------------------------------------
Simple assume observe*         1     false     4.63 ns       12.81    1539.11       35.23     12.67
Simple assume observe*         1      true     4.63 ns       12.62    1697.66       38.46     12.51
Smorgasbord                  201     false      6.0 μs       71.62     133.56        6.84      9.55
Smorgasbord                  201      true     7.57 μs       77.29     143.33        6.21      6.95
Loop univariate 1k          1000     false     17.8 μs      974.25     304.93        8.02      6.43
Loop univariate 1k          1000      true     19.1 μs     1381.55     283.92        7.47      6.00
Multivariate 1k             1000     false     23.1 μs      314.22      73.84        9.58      3.27
Multivariate 1k             1000      true     25.8 μs      312.72      62.50        8.82      3.02
Loop univariate 10k        10000     false    174.0 μs    12372.03     327.95        8.12      6.56
Loop univariate 10k        10000      true    186.0 μs    11744.23     312.28        7.81      6.13
Multivariate 10k           10000     false    197.0 μs     5625.04      89.38       11.54      2.29
Multivariate 10k           10000      true    197.0 μs     5069.38      90.19       11.46      2.33
Dynamic                       15     false     1.39 μs         err      46.38       15.16     11.60
Dynamic                       10      true     1.94 μs        2.08      56.85       19.01     19.19
Submodel*                      1     false     4.64 ns       12.01    1793.96       35.87     15.70
Submodel*                      1      true     4.65 ns       12.57    1821.70       35.00     12.27
LDA                           12      true     23.1 μs        0.68       2.11       32.46       err
===================================================================================================

Main @ a115fa8

===================================================================================================
                                               eval                       gradient                 
                                            ----------  -------------------------------------------
Model                        dim    linked      primal     FwdDiff    RvsDiff    Mooncake    Enzyme
---------------------------------------------------------------------------------------------------
Simple assume observe*         1     false     3.83 ns       13.45    1942.68       77.65     28.36
Simple assume observe*         1      true     3.83 ns       29.63    2313.62       77.05     27.89
Smorgasbord                  201     false     11.7 μs       38.22      67.90        6.09      5.06
Smorgasbord                  201      true     14.5 μs       37.49      67.72        5.39      4.05
Loop univariate 1k          1000     false     43.6 μs      436.35     119.95        4.02      3.15
Loop univariate 1k          1000      true     43.2 μs      625.81     123.54        3.98      3.14
Multivariate 1k             1000     false     39.7 μs      251.89      39.51        5.60      1.82
Multivariate 1k             1000      true     42.1 μs      227.86      39.89        4.46      1.90
Loop univariate 10k        10000     false    191.0 μs    14050.98     292.44        7.33      7.08
Loop univariate 10k        10000      true    207.0 μs    14681.75     284.78        6.94      6.54
Multivariate 10k           10000     false    239.0 μs     8823.49      72.03        9.38      1.82
Multivariate 10k           10000      true    243.0 μs     8659.63      71.57       10.46      1.85
Dynamic                       15     false     2.41 μs         err      35.61       12.37      8.50
Dynamic                       10      true     3.28 μs        1.87      39.15       10.85     17.82
Submodel*                      1     false     3.84 ns       29.72    2305.11       74.51     26.99
Submodel*                      1      true     3.83 ns       29.59    3020.05       77.86     28.28
LDA                           12      true     28.5 μs        0.63       2.50       20.99       err
===================================================================================================

Environment

Julia Version 1.11.9
Commit 53a02c0720c (2026-02-06 00:27 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)

[yebai]

Thanks @shravanngoswamii!