#7016 Fix bundled library subpath serialization

Summary

Fixes issue #6975.

compile_app() was clearing explicit bundle_library() registrations during frontend compilation. Dynamic components
also failed to rewrite bundled library subpath imports, such as Lucide deep imports.

Changes

• Preserve user-registered bundled libraries during compilation.
• Rewrite bundled default, named, and namespace subpath imports through window.__reflex.
• Add unit tests for bundled-library preservation and subpath serialization.
• Add browser integration coverage using a dynamically rendered Lucide icon.
• Add required bugfix news fragments.

Tests

• uv run pytest tests/units/compiler/test_dynamic_components_codegen.py tests/units/compiler/test_compiler.py -q
• uv run pytest tests/integration/test_dynamic_components.py -q
• Ruff checks and formatting pass.
• Pyright passes for the changed source modules.