Reverts 259 files that carried unrelated upstream changes through the
phase-6 merge: enum class removals (cppcoreguidelines-use-enum-class),
scoped_lock→lock_guard conversions (modernize-use-scoped-lock),
nodestore Backend API changes (void const* key), .clang-tidy config,
test infrastructure deletions, and miscellaneous develop changes.
These changes belong on develop, not in the telemetry PR chain.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This change:
* Introduces a new helper function on `STTx`, `getFeePayer`.
* Removes the usage of `mSourceBalance` and replaces it with SLE balance lookups.
* Renames `mPriorBalance` to `preFeeBalance_`
This simplifies some of the code in the transactors and makes it a lot more readable.
