Standalone configuration is dev oriented

The current standalone CMake configuration is optimized for internal development rather than for clients who want to consume the library as an independent module. When selecting standalone mode, users reasonably expect that development‑only features are disabled. Instead, several dev‑oriented settings remain active, including:

• verbose and trace logging
• test builds
• (options to enable) ASAN and other sanitizers/checks
• ...

For consumers, the standalone configuration should produce only the client‑facing library with all development features turned off by default.
To address this, explicit development mode might need to be introduced separate from the standalone mode. This would cleanly separate client builds from internal development workflows.

Additionally, users currently cannot disable standalone mode because a shadowed variable overrides the user‑provided input. A fix for this issue is already available here.

Start by inspecting the standalone CMake configuration and the shadowed variable described in the issue and linked pull request. Determine how standalone mode enables logging, tests, sanitizers, and other development settings; done means consumer builds disable those features by default and users can disable standalone mode reliably.