gh-152297: Reify dotted lazy imports with the full dotted name

[Kuhai9801]

For lazy import pkg.sub, the reifier shortened the name passed to __import__ to pkg. Eager import pkg.sub passes pkg.sub and lets the import protocol return the object to bind.

Pass the stored full import name during lazy reification. Add regressions for custom __import__ hooks and for loading the submodule on first use.

Tests:

• git diff --check
• python -m py_compile Lib/test/test_lazy_import/__init__.py

• Issue: Dotted lazy import reification bypasses full-name __import__ hook #152297

[python-cla-bot]

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