ERROR: InitError: expected package `Measurements [eff96d63]` to exist in the manifest

```julia
(@BjetTLA) pkg> rm Measurements
Updating `~/.julia/environments/BjetTLA/Project.toml`
[eff96d63] - Measurements v2.14.0
No Changes to `~/.julia/environments/BjetTLA/Manifest.toml`

julia> using PythonCall

julia> #works fine
```

```julia
(@BjetTLA) pkg> add Measurements
Resolving package versions...
Compat entries added for Measurements
Updating `~/.julia/environments/BjetTLA/Project.toml`
[eff96d63] + Measurements v2.14.0
No Changes to `~/.julia/environments/BjetTLA/Manifest.toml`
Precompiling project...
✗ SciMLBase → SciMLBasePythonCallExt
✗ BjetTLA
0 dependencies successfully precompiled in 34 seconds. 655 already precompiled.
2 dependencies errored.
For a report of the errors see `julia> err`. To retry use `pkg> precompile`

[jiling@jiling-notebook-1 BjetTLA]$ julia --project
_
_ _ _(_)_ | Documentation: https://docs.julialang.org
(_) | (_) (_) |
_ _ _| |_ __ _ | Type "?" for help, "]?" for Pkg help.
| | | | | | |/ _` | |
| | |_| | | | (_| | | Version 1.11.6 (2025-07-09)
_/ |\__'_|_|_|\__'_| | Official https://julialang.org/ release
|__/ |

julia> using PythonCall
CondaPkg Found dependencies: /home/jiling/.julia/environments/BjetTLA/CondaPkg.toml
ERROR: InitError: expected package `Measurements [eff96d63]` to exist in the manifest (use `resolve` to populate the manifest)
Stacktrace:
[1] pkgerror(::String, ::Vararg{String})
@ Pkg.Types ~/.julia/juliaup/julia-1.11.6+0.x64.linux.gnu/share/julia/stdlib/v1.11/Pkg/src/Types.jl:68
[2] package_info
@ ~/.julia/juliaup/julia-1.11.6+0.x64.linux.gnu/share/julia/stdlib/v1.11/Pkg/src/API.jl:56 [inlined]
[3] #9
@ ./none:0 [inlined]
[4] iterate
@ ./generator.jl:48 [inlined]
[5] Dict{Base.UUID, Pkg.API.PackageInfo}(kv::Base.Generator{Vector{Pkg.Types.PackageSpec}, Pkg.API.var"#9#10"{Pkg.Types.EnvCache}})
@ Base ./dict.jl:95
[6] dict_with_eltype
@ ./abstractdict.jl:636 [inlined]
[7] dict_with_eltype
@ ./abstractdict.jl:643 [inlined]
```

Reproduce the failure with Julia 1.11.6 in the BjetTLA project by removing and re-adding Measurements, then running `using PythonCall`. Compare the Project.toml and Manifest.toml state and retry precompilation; done means PythonCall loads without the Measurements InitError and the project precompiles successfully.

Written by the indexing model from the issue text.