Add Python API reference docs and generation script for ADK Python 2.0.0 (#1786)

* Add Python API docs generation script and Sphinx config

* Add Python API reference docs for ADK Python 2.0.0

* Include version and release number in config for built API docs

Author: koverholt

docs/api-reference/python/_sources/google-adk.rst.txt

@@ -1,19 +1,3 @@
-/**
- * Copyright 2026 Google LLC
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
 .autodoc_pydantic_validator_arrow {
   padding-left: 8px;
   }
@@ -24,4 +8,4 @@
 
 .autodoc_pydantic_collapsable_erd {
   cursor: pointer;
-  }
+  }

docs/api-reference/python/_sources/index.rst.txt

@@ -903,4 +903,4 @@ div.math:hover a.headerlink {
     #top-link {
         display: none;
     }
-}
+}

docs/api-reference/python/_static/autodoc_pydantic.css

@@ -1,5 +1,5 @@
 const DOCUMENTATION_OPTIONS = {
-    VERSION: '',
+    VERSION: '2.0.0',
     LANGUAGE: 'en',
     COLLAPSE_INDEX: false,
     BUILDER: 'html',

docs/api-reference/python/_static/basic.css

@@ -189,3 +189,4 @@ var Stemmer = function() {
     return w;
   }
 }
+