[docs] simplify sidebar navigation (#7070)

Author: blinkov

ydb/docs/en/core/concepts/auth.md

@@ -4,7 +4,7 @@ Once a network connection is established, the server starts to accept client req
 
 The following authentication modes are supported:
 
-* Anonymous access is enabled by default and available immediately when you [install the cluster](../deploy/index.md).
+* Anonymous access is enabled by default and available immediately when you [install the cluster](../devops/index.md).
 * [Authentication through a third-party IAM provider](#iam), for example, [Yandex Identity and Access Management]{% if lang == "en" %}(https://cloud.yandex.com/en/docs/iam/){% endif %}{% if lang == "ru" %}(https://cloud.yandex.ru/docs/iam/){% endif %}.
 * Authentication by [username and password](#static-credentials).
 

ydb/docs/en/core/concepts/datamodel/toc_i.yaml

@@ -1,5 +1,4 @@
 items:
-- { name: Overview,                                  href: index.md }
 - { name: Directory,                                 href: dir.md }
 - { name: Table,                                     href: table.md }
 - { name: View,                                      href: view.md }

ydb/docs/en/core/concepts/toc_i.yaml

@@ -1,10 +1,10 @@
 items:
-- { name: Overview,                                  href: index.md }
 - { name: Glossary,                  href: glossary.md }
 - { name: Connecting to a database,       href: connect.md }
 - name: Authentication
   href: auth.md
 - name: Data model and schema
+  href: datamodel/index.md
   include: { path: datamodel/toc_p.yaml, mode: link }
 - { name: Transactions,                             href: transactions.md }
 - { name: Secondary indexes,                      href: secondary_indexes.md }
@@ -14,9 +14,8 @@ items:
 - { name: Database limits,                href: limits-ydb.md }
 - { name: Multi-Version Concurrency Control (MVCC), href: mvcc.md }
 - name: YDB cluster
+  href: cluster/index.md
   items:
-  - name: Overview
-    href: cluster/index.md
   - name: Topology
     href: topology.md
   - name: General YDB schema

ydb/docs/en/core/contributor/toc_i.yaml

@@ -18,9 +18,8 @@ items:
     - name: Distributed transactions
       href: datashard-distributed-txs.md
   - name: Testing with load actors
+    href: load-actors-overview.md
     items:
-    - name: Overview
-      href: load-actors-overview.md
     - name: KqpLoad
       href: load-actors-kqp.md
     - name: KeyValueLoad

ydb/docs/en/core/contributor/toc_p.yaml

@@ -1,4 +1,2 @@
 items:
-- name: Overview
-  href: index.md
 - include: { mode: link, path: toc_i.yaml }

ydb/docs/en/core/deploy/_includes/index.md

@@ -1,6 +1,4 @@
 items:
-#- name: Overview
-#  href: concepts.md
 - name: Deployment
   href: deploy-ydb-on-premises.md
 - name: Deployment with Federated Query

ydb/docs/en/core/deploy/index.md

@@ -1,4 +1,2 @@
 items:
-- name: Overview
-  href: index.md
 - include: { mode: link, path: toc_i.yaml }

ydb/docs/en/core/deploy/manual/toc_i.yaml

@@ -1,6 +1,4 @@
 items:
-- name: Overview
-  href: index.md
 - name: C++
   href: example-cpp.md
 - name: C# (.NET)