Migrate 27 queries under python/ql/src/ from legacy CFG types
(CallNode/AttrNode/NameNode/etc.) to the shared-CFG-based 'Cfg::'
namespace, matching the dataflow API surface introduced earlier on
this branch. ModificationOfParameterWithDefaultCustomizations.qll
is rewritten on top of BarrierGuard, removing the last legacy ESSA
dependency in that file. UnguardedNextInGenerator.ql still uses
ESSA and bridges to the new CFG via Cfg::CallNode.getNode().
Also reformat 14 library and query files that had drifted from
the formatter.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Moves the existing points-to predicates to the newly added class
`ControlFlowNodeWithPointsTo` which resides in the `LegacyPointsTo`
module.
(Existing code that uses these predicates should import this module, and
references to `ControlFlowNode` should be changed to
`ControlFlowNodeWithPointsTo`.)
Also updates all existing points-to based code to do just this.
