fixed: added header to the built-in sources and edited the sidebar

Author: esther-anierobi

docs/docs/sources/AmazonS3.md

@@ -1,4 +1,8 @@
-## AmazonS3
+---
+title: AmazonS3
+description: CocoIndex AmazonS3 sources
+toc_max_heading_level: 4
+---
 
 ### Setup for Amazon S3
 
@@ -114,4 +118,4 @@ The spec takes the following fields:
 The output is a [*KTable*](/docs/core/data_types#ktable) with the following sub fields:
 
 *   `filename` (*Str*, key): the filename of the file, including the path, relative to the root directory, e.g. `"dir1/file1.md"`.
-*   `content` (*Str* if `binary` is `False`, otherwise *Bytes*): the content of the file
+*   `content` (*Str* if `binary` is `False`, otherwise *Bytes*): the content of the file

docs/docs/sources/AzureBlob.md

@@ -1,4 +1,8 @@
-## AzureBlob
+---
+title: AzureBlob
+description: CocoIndex AzureBlob sources
+toc_max_heading_level: 4
+---
 
 The `AzureBlob` source imports files from Azure Blob Storage.
 

docs/docs/sources/GoogleDrive.md

@@ -1,4 +1,8 @@
-## GoogleDrive
+---
+title: GoogleDrive
+description: CocoIndex GoogleDrive sources
+toc_max_heading_level: 4
+---
 
 The `GoogleDrive` source imports files from Google Drive.
 

docs/docs/sources/LocalFile.md

@@ -1,4 +1,8 @@
-## LocalFile
+---
+title: LocalFile
+description: CocoIndex LocalFile sources
+toc_max_heading_level: 4
+---
 
 The `LocalFile` source imports files from a local file system.
 
@@ -23,4 +27,4 @@ The spec takes the following fields:
 
 The output is a [*KTable*](/docs/core/data_types#ktable) with the following sub fields:
 *   `filename` (*Str*, key): the filename of the file, including the path, relative to the root directory, e.g. `"dir1/file1.md"`
-*   `content` (*Str* if `binary` is `False`, *Bytes* otherwise): the content of the file
+*   `content` (*Str* if `binary` is `False`, *Bytes* otherwise): the content of the file

docs/docs/sources/built-in-source.md

@@ -1,4 +1,8 @@
-## Postgres
+---
+title: Postgres
+description: CocoIndex Postgres Sources
+toc_max_heading_level: 4
+---
 
 The `Postgres` source imports rows from a PostgreSQL table.
 
@@ -59,4 +63,4 @@ The output is a [*KTable*](/docs/core/data_types#ktable) with straightforward 1
 ### Example
 
 You can find end-to-end example using Postgres source at:
-*   [examples/postgres_source](https://github.com/cocoindex-io/cocoindex/tree/main/examples/postgres_source)
+*   [examples/postgres_source](https://github.com/cocoindex-io/cocoindex/tree/main/examples/postgres_source)