Introduce navigation_startdepth parameter

Allows users to start the sidebar Toc at level 0

Addresses issue pydata#1181

Author: SimenZhor

docs/conf.py

@@ -145,6 +145,7 @@
     "navbar_align": "left",  # [left, content, right] For testing that the navbar items align properly
     "navbar_center": ["version-switcher", "navbar-nav"],
     "announcement": "https://raw.githubusercontent.com/pydata/pydata-sphinx-theme/main/docs/_templates/custom-template.html",
+    "navigation_startdepth": 0,
     # "show_nav_level": 2,
     # "navbar_start": ["navbar-logo"],
     # "navbar_end": ["theme-switcher", "navbar-icon-links"],

src/pydata_sphinx_theme/theme/pydata_sphinx_theme/layout.html

@@ -10,6 +10,7 @@
 {# Create the sidebar links HTML here to re-use in a few places #}
 {# If we have no sidebar links, pop the links component from the sidebar list #}
 {%- set sidebar_nav_html = generate_toctree_html("sidebar",
+startdepth=theme_navigation_startdepth|int,
 show_nav_level=theme_show_nav_level|int,
 maxdepth=theme_navigation_depth|int,
 collapse=theme_collapse_navigation|tobool,

src/pydata_sphinx_theme/theme/pydata_sphinx_theme/theme.conf

@@ -25,6 +25,7 @@ search_bar_text = Search the docs ...
 search_bar_position = sidebar
 navigation_with_keys = True
 collapse_navigation = False
+navigation_startdepth = 1
 navigation_depth = 4
 show_nav_level = 1
 show_toc_level = 1