Add tutorial and update documentation

[hfern]

Removes the caveat about not being able to get production, as I feel that's now a viable path.
Switches recommendation from using nuitka to pex, which I have had good experience with.
Adds a simple step-by-step tutorial for starting a new provider. It's modeled on the e2e example.

See the docs preview at: https://python-tf--14.org.readthedocs.build/en/14/index.html

[Copilot]

Pull Request Overview

This PR adds comprehensive documentation improvements including a new tutorial for creating providers and updates recommendations for building production binaries. The changes shift the focus from discouraging production use to providing practical guidance.

• Adds a step-by-step tutorial for creating a math provider with data sources
• Updates binary building recommendations from Nuitka to Pex
• Removes production warnings and adds tips/tricks documentation

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tf/types.py	Improves documentation for the Unknown sentinel value
tf/iface.py	Moves type alias definitions above their docstrings for better code organization
src/tf/init.py	Adds a simple main function placeholder
docs/tutorial.rst	Comprehensive new tutorial covering provider creation from setup to data sources
docs/tips_tricks.rst	New documentation for debugging and binary building guidance
docs/index.rst	Updates table of contents and removes production warning
docs/caveats.md	Updates binary building recommendations from Nuitka to Pex
docs/api.rst	Expands API documentation with better explanations and Config type documentation
CHANGELOG.md	Documents the addition of the tutorial

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