feat(docs): replace hand-written method pages with griffe + pre-renderer pipeline

Replace 136 manually maintained method documentation pages with a directive-based
system where signature, parameters, and returns are auto-generated from code
docstrings via griffe static AST analysis.

Key changes:

- Add griffe_builder.py: static AST replacement for json_builder.py — produces
  identical data.json without requiring package installation (~1.1s vs ~1.8s)
- Add method_page_renderer.py: pre-renders method pages from api_ref frontmatter,
  with type names hyperlinked to API reference pages via links.json
- Add migrate_method_pages.py: one-time migration that converted 136 pages to
  api_ref directive format, preserving hand-written Example sections
- Update python_ref_builder.py: fix dedup bug that skipped recursion into
  duplicate-named modules (e.g. CatalogWorkspace was unreachable), add
  --export-links flag to export type->URL mapping for method_page_renderer
- Update generate.sh and generate-single-version.sh: prefer griffe over legacy
  json_builder, call method_page_renderer with --links-json
- Fix 9 docstrings with invalid "Args: None" pattern and 3 with missing blank
  lines before Args/Returns sections
- Delete 12 unused Hugo shortcode/partial templates (api-ref-*, parameter*)
- Add 91 unit tests (up from 33) covering griffe builder, method renderer,
  link resolution, frontmatter parsing, idempotency, and edge cases
- Update scripts/docs/README.md with new pipeline documentation

jira: trivial
risk: nonprod

Author: hkad98