Refactor html_generation into subpackage with clean public API

- Move renderer, generator, templates, static/, and Jinja2 templates
  into html_generation/ subpackage
- Expose public API via html_generation/__init__.py (Session, Project,
  generate_html, generate_batch_html, inject_gist_preview_js, create_gist)
- Prefix all internal names with _ across renderer, generator, templates
- Add Session/Project dataclasses; callers now build and pass these in,
  removing parse_session_file from generator
- parse_session_file now returns loglines list directly instead of dict
- Move detect_github_repo into generator as _detect_github_repo,
  removing the html_generation -> api dependency
- Add Windows/Linux support for cowork sessions via platformdirs
- Handle _audit_timestamp fallback and isMeta/isSynthetic skipping
  in parser
- Add platformdirs dependency

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: zackman0010

.idea/.gitignore

@@ -6,7 +6,7 @@ Run the development version of the tool like this:
 
     uv run claude-code-transcripts --help
 
-Always practice TDD: write a faliing test, watch it fail, then make it pass.
+Always practice TDD: write a failing test, watch it fail, then make it pass.
 
 Commit early and often. Commits should bundle the test, implementation, and documentation changes together.
 

.idea/claude-code-transcripts.iml

@@ -14,6 +14,7 @@ dependencies = [
     "httpx",
     "jinja2",
     "markdown",
+    "platformdirs",
     "questionary",
 ]