Add documentation & HTTP status FormNotFoundError now 404

[Mark90]

Summary

Add documentation to the project and make it work as a subproject of https://github.com/workfloworchestrator/workfloworchestrator.github.io.

Initial documentation generated with Claude Code followed by lots of redactions.

Code blocks in the markdown documentation consist of normal python blocks followed by pycon (Python Console) blocks which demonstrate assertions on previous code blocks, and which are validated through a unit test / pre-commit hook.

Code changes

• Form generator now raises FormNotFoundError instead of FormException
• FormPage.meta__ now a default ClassVar (no impact on schema or serialization) and documented
• form_error_handler reworked and added handling of FormNotFoundError (404 now instead of 500)
• Lots of docstrings

Screenshots

Intro page

Usage

Examples

Reference page

Search (project name prefix is a CSS hack, see monorepo PR )

Neat unexpected side-effect (might be a bit hard to see): mkdocs is now able link from orchestrator-core's reference docs to a type in pydantic-forms that it uses

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.52%. Comparing base (27ee42d) to head (2ab8a1e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #69      +/-   ##
==========================================
+ Coverage   91.82%   94.52%   +2.70%     
==========================================
  Files          33       33              
  Lines         697      731      +34     
  Branches       71       71              
==========================================
+ Hits          640      691      +51     
+ Misses         52       31      -21     
- Partials        5        9       +4     

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[eenblam]

I haven't had time to exercise this locally today, but it looks good! I left some comments with suggestions and questions, but I don't see any of them as blocking.