Update Documentation for Join Condition Query Strings

[ZaidMaslouhi]

Issue Description

The documentation for join conditions in query strings was unclear, leading to potential confusion for users.

Changes

• Updated documentation to clarify the correct query string format for join conditions
• Added example showing the recommended syntax with square brackets
• Highlighted the preferred method of using join[] in query strings

Example

Before:
join=facilities||id,status||on[0]=facilities.status||$eq||Archived

After:
join[]=facilities||id,status||on[0]=facilities.status||$eq||Archived

Reasoning

The updated documentation now explicitly shows the recommended way to construct join condition query strings to ensure correct parsing.

Related Issue

Closes #53

[zaro]

@ZaidMaslouhi thanks for the clarification