Snake Case to Camel Case with Repository-Wide Refactor

Convert a valid snake_case identifier to camelCase, then design a safe repository-wide migration for variables and function names without changing third-party symbols, public interfaces, or the tests' ability to detect regressions. Requirements Implement a conversion from a valid snake_case identifier to camelCase. The base input is guaranteed valid: no leading underscore, trailing underscore, or doubled separator. Example: foo_bar -> fooBar. Extend the discussion to a repository too large for manual review: replace snake-case variables and functions across the codebase. Explain how to verify that the repository still works after the automated rewrite, including when test-package identifiers are rewritten too. Preserve third-party functions and public interfaces; explain how the migration distinguishes symbols that may change from contracts that must remain stable. Examples foo_bar -> fooBar Notes The implementation is intentionally short. Most of the round is spent on scoping a safe refactor, validation strategy, symbol ownership, and compatibility boundaries. Clarify whether names appear only as parsed identifiers or may also occur in strings, generated code, configuration, reflection, and serialized data. A text replacement is not enough to distinguish local symbols from external APIs or public contracts. Preparation Implement the identifier conversion and enumerate edge cases before expanding scope. Rehearse a migration plan covering symbol-aware rewriting, build and test validation, staged rollout, compatibility shims, and rollback.