Remove the deprecation proxy infrastructure that allowed old-style flat
imports (e.g. `from pipecat.services.openai import OpenAILLMService`).
Users must now import from specific submodules
(`from pipecat.services.openai.llm import OpenAILLMService`), which is
already the established pattern across all internal code and 179+ examples.
- Strip 32 proxy `__init__.py` files to empty
- Strip 3 non-proxy files with bare star imports (minimax, sambanova, sarvam)
- Strip google/gemini_live `__init__.py` re-exports
- Remove DeprecatedModuleProxy class and helpers from services/__init__.py
- Remove ruff per-file ignore for services/__init__.py
- Fix 2 examples using old-style imports
Example files like openai.py shadow installed packages when Python adds the
script directory to sys.path. Prepend the parent folder name to each example
file (e.g. openai.py -> function-calling-openai.py). Also split
thinking-and-mcp/ into separate mcp/ and thinking/ directories.
