special-case implicit-bool to exclude commonly-used patterns

### Describe the Bug

reduce the noise, and skip the error if the value is one of the following:
- union between always-truthy classes & None
- certain container classes (how do we detect this - hardcoded list or some parent class? what is included?)

### Sandbox Link

_No response_

### (Only applicable for extension issues) IDE Information

_No response_

The issue names no files, tests, or entry points. Start by locating the implicit-bool diagnostic and the type-checking logic for unions and containers; clarify which always-truthy classes and container classes are in scope, then add coverage showing the specified patterns no longer produce the error.

Written by the indexing model from the issue text.