add nested READMEs to navigation

Author: SiyaoIsHiding

mkdocs.yml

@@ -16,7 +16,6 @@ theme:
   features:
     - navigation.tabs
     - navigation.sections
-    - navigation.expand
     - navigation.top
     - search.highlight
     - search.share
@@ -49,7 +48,12 @@ nav:
       - Speculative Execution: core/speculative_execution/README.md
       - Metrics: core/metrics/README.md
       - Logging: core/logging/README.md
-      - Statements: core/statements/README.md
+      - Statements:
+        - Overview: core/statements/README.md
+        - Batch: core/statements/batch/README.md
+        - Per Query Keyspace: core/statements/per_query_keyspace/README.md
+        - Prepared: core/statements/prepared/README.md
+        - Simple: core/statements/simple/README.md
       - Paging: core/paging/README.md
       - Async Programming: core/async/README.md
       - Reactive Streams: core/reactive/README.md
@@ -63,14 +67,29 @@ nav:
       - Throttling: core/throttling/README.md
       - Tracing: core/tracing/README.md
       - Performance: core/performance/README.md
-      - Metadata: core/metadata/README.md
+      - Metadata:
+        - Overview: core/metadata/README.md
+        - Node: core/metadata/node/README.md
+        - Schema: core/metadata/schema/README.md
+        - Token: core/metadata/token/README.md
       - Control Connection: core/control_connection/README.md
       - Native Protocol: core/native_protocol/README.md
       - Non-blocking: core/non_blocking/README.md
       - Query Timestamps: core/query_timestamps/README.md
       - Idempotence: core/idempotence/README.md
       - Detachable Types: core/detachable_types/README.md
-      - DSE: core/dse/README.md
+      - DSE:
+        - Overview: core/dse/README.md
+        - Geotypes: core/dse/geotypes/README.md
+        - Graph:
+          - Overview: core/dse/graph/README.md
+          - Fluent:
+            - Overview: core/dse/graph/fluent/README.md
+            - Explicit: core/dse/graph/fluent/explicit/README.md
+            - Implicit: core/dse/graph/fluent/implicit/README.md
+          - Options: core/dse/graph/options/README.md
+          - Results: core/dse/graph/results/README.md
+          - Script: core/dse/graph/script/README.md
       - GraalVM: core/graalvm/README.md
       - Shaded JAR: core/shaded_jar/README.md
       - BOM: core/bom/README.md
@@ -80,7 +99,15 @@ nav:
       - Insert: query_builder/insert/README.md
       - Update: query_builder/update/README.md
       - Delete: query_builder/delete/README.md
-      - Schema: query_builder/schema/README.md
+      - Schema:
+        - Overview: query_builder/schema/README.md
+        - Aggregate: query_builder/schema/aggregate/README.md
+        - Function: query_builder/schema/function/README.md
+        - Index: query_builder/schema/index/README.md
+        - Keyspace: query_builder/schema/keyspace/README.md
+        - Materialized View: query_builder/schema/materialized_view/README.md
+        - Table: query_builder/schema/table/README.md
+        - Type: query_builder/schema/type/README.md
       - Truncate: query_builder/truncate/README.md
       - Condition: query_builder/condition/README.md
       - Relation: query_builder/relation/README.md
@@ -89,12 +116,34 @@ nav:
     - Mapper:
       - Overview: mapper/README.md
       - Entities: mapper/entities/README.md
-      - DAOs: mapper/daos/README.md
+      - DAOs:
+        - Overview: mapper/daos/README.md
+        - Custom Types: mapper/daos/custom_types/README.md
+        - Delete: mapper/daos/delete/README.md
+        - Get Entity: mapper/daos/getentity/README.md
+        - Increment: mapper/daos/increment/README.md
+        - Insert: mapper/daos/insert/README.md
+        - Null Saving: mapper/daos/null_saving/README.md
+        - Query: mapper/daos/query/README.md
+        - Query Provider: mapper/daos/queryprovider/README.md
+        - Select: mapper/daos/select/README.md
+        - Set Entity: mapper/daos/setentity/README.md
+        - Statement Attributes: mapper/daos/statement_attributes/README.md
+        - Update: mapper/daos/update/README.md
       - Mapper: mapper/mapper/README.md
-      - Configuration: mapper/config/README.md
+      - Configuration:
+        - Overview: mapper/config/README.md
+        - Kotlin: mapper/config/kotlin/README.md
+        - Lombok: mapper/config/lombok/README.md
+        - Record: mapper/config/record/README.md
+        - Scala: mapper/config/scala/README.md
     - Developer:
       - Overview: developer/README.md
-      - Common: developer/common/README.md
+      - Common:
+        - Overview: developer/common/README.md
+        - Concurrency: developer/common/concurrency/README.md
+        - Context: developer/common/context/README.md
+        - Event Bus: developer/common/event_bus/README.md
       - Native Protocol: developer/native_protocol/README.md
       - Netty Pipeline: developer/netty_pipeline/README.md
       - Request Execution: developer/request_execution/README.md