Guards: Generalise ValidationWrapper to support GuardValue-based BarrierGuards

[aschackmull]

First commit as the title says - in particular, this allows BarrierGuards that work like assertions, i.e. they potentially throw instead of returning a boolean.
Second commit renames the module as the WithState naming felt a bit too constrained - it's not just (flow-)state, it's a general parameter that can be used for whatever.

[Copilot]

Pull request overview

This PR generalizes the ValidationWrapper module in the Guards library to support GuardValue-based barrier guards and renames related components to better reflect their general parameter usage rather than being constrained to flow-state.

• Changes the guardChecksSig signature from accepting boolean branch to accepting GuardValue gv
• Renames StateSig to ParamSig, WithState to WithParam, and ValidationWrapperWithState to ParameterizedValidationWrapper
• Updates Java and C++ implementations to adapt to the new GuardValue-based interface

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
shared/controlflow/codeql/controlflow/Guards.qll	Generalizes validation wrapper signatures to use GuardValue instead of boolean, and renames state-related identifiers to more general parameter naming
java/ql/lib/semmle/code/java/dataflow/internal/SsaImpl.qll	Adds adaptation layer to convert from boolean-based guard checks to GuardValue-based interface
cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/SsaImpl.qll	Updates module references and adds adaptation layer for GuardValue-based interface

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[hvitved]

LGTM, but could we have a test case?

[hvitved]

Also, remember to run DCA.