Fix/update subsolver api docs (#149)

* docs(advanced-jsosolvers): update TRUNK subsolver usage to new keyword API and add note on allowed subsolvers and tolerances (fixes #145)

* docs(advanced-jsosolvers): add concise migration note (old subsolver_type => new subsolver=:symbol)

* docs(intro): add migration note for subsolver API (subsolver_type => subsolver = :symbol)

* docs(intro): show how to list allowed subsolvers for trunk/tron least-squares variants

* docs(intro): add example of trunk with explicit subsolver and tolerances

* docs(advanced-jsosolvers): add explicit trunk call with subsolver and tolerances

* docs(advanced-jsosolvers): mention TRON uses same subsolver keyword pattern with example

* docs: copy edits and grammar fixes in advanced and intro tutorials

* test: make tutorial checks robust (require index.jmd and Project.toml only); docs: minor copy edits

* docs(advanced-jsosolvers): add link to Krylov.jl docs for subsolver algorithm details

* Update tutorials/advanced-jsosolvers/index.jmd

Co-authored-by: Tangi Migot <tangi.migot@gmail.com>

* Update tutorials/advanced-jsosolvers/index.jmd

Co-authored-by: Tangi Migot <tangi.migot@gmail.com>

* Update tutorials/introduction-to-jsosolvers/index.jmd

Co-authored-by: Tangi Migot <tangi.migot@gmail.com>

* Update runtests.jl

* Update index.jmd

* Update index.jmd

* Update index.jmd

---------

Co-authored-by: Tangi Migot <tangi.migot@gmail.com>

Author: arnavk23

tutorials/introduction-to-jsosolvers/index.jmd

@@ -44,6 +44,13 @@ The solvers `tron` and `trunk` both have a specialized implementation for input
 
 The following examples illustrate this specialization.
 
+To list the allowed least-squares subsolvers for these specializations:
+
+```julia
+JSOSolvers.trunkls_allowed_subsolvers
+JSOSolvers.tronls_allowed_subsolvers
+```
+
 ```julia
 using JSOSolvers, ADNLPModels
 f(x) = (x[1] - 1)^2 + 4 * (x[2] - x[1]^2)^2
@@ -111,7 +118,7 @@ solver = LBFGSSolver(nlp; mem = 5);
 stats = solve!(solver, nlp)
 ```
 
-The following table provides the correspondance between the solvers and the solvers structures:
+The following table provides the correspondence between the algorithms and their solver structures:
 
 | Algorithm           | Solver structure |
 | ------------------- | ---------------- |