feat(docs): D-19 Add Contract Documentation Generator

[damiedee96]

Closes #356
Implements the full contract documentation generator pipeline as described in issue #356 (D-19).

New modules:

• src/utils/doc_extractor.rs - Extracts doc comments (///, //!) and
  code examples from .rs source files
• src/utils/doc_templates.rs - Template system (HtmlFull, HtmlCard,
  MarkdownFull, MarkdownSummary, Custom)
  with {{placeholder}} rendering
• src/utils/doc_html.rs - HTML site generator; produces per-contract
  pages and a searchable portal index
• src/utils/doc_api_ref.rs - Machine-readable API reference builder;
  emits JSON + GitHub-flavoured Markdown
• src/utils/doc_publisher.rs - Publish pipeline supporting Local, GitHub
  Pages, and custom HTTP targets with a
  persistent publish log

Updated:

• src/utils/mod.rs - Registers the five new utility modules
• src/commands/docs.rs - Expands 'starforge docs' with new subcommands:
  extract, html, api-ref, publish

New CLI subcommands:
starforge docs extract Extract doc comments from source
starforge docs html Generate HTML documentation site
starforge docs api-ref Generate JSON + Markdown API ref
starforge docs publish Full build + publish pipeline

Existing subcommands retained:
generate, show, list, search, versions, export

All new modules include unit tests.

Closes #356

Description

Brief description of what this PR does and why.

Closes #(issue number)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Changes Made

• Change 1
• Change 2
• Change 3

Testing

How has this been tested?

Describe the tests you ran and how to reproduce them.

• Unit tests added/updated
• Integration tests added/updated
• Manual testing performed

Test Coverage

Describe what scenarios have been tested:

• Happy path:
• Edge cases:
• Error handling:

Code Quality Checklist

• My code follows the style guidelines of this project (cargo fmt)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings (cargo clippy -- -D warnings)
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• The CI checks pass (format, clippy, tests)

Breaking Changes

• This PR introduces breaking changes

If checked, describe the breaking changes and migration path:

Documentation

• README.md updated
• DEVELOPER_GUIDE.md updated (if applicable)
• API_REFERENCE.md updated (if applicable)
• No documentation changes needed

Screenshots (if applicable)

Add screenshots or GIFs for UI changes.

Additional Context

Add any other context about the PR here.

---

Note: Make sure all tests pass locally before submitting:

cargo test
cargo fmt --all
cargo clippy -- -D warnings

[drips-wave]

@damiedee96 Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits