docs: Clarify case sensitivity behavior for JSON keys vs object properties

docs/for-template-authors/best-practices.md

@@ -273,12 +273,14 @@ Always validate your JSON before using it with Templify:
 
 ### Double-Check Placeholder Names
 
-**Case-sensitive matching:**
+**JSON keys are case-sensitive:**
 - Template: `{{CustomerName}}`
 - JSON: `"CustomerName"` ✅
 - JSON: `"customername"` ❌
 - JSON: `"customer_name"` ❌
 
+Always match the exact case from your JSON data.
+
 ### Verify Closing Tags
 
 Every opening tag needs a closing tag:

docs/for-template-authors/placeholders.md

@@ -418,7 +418,9 @@ Empty strings are replaced with nothing (empty text).
 
 ### Case Sensitivity
 
-Remember that placeholder names are case-sensitive:
+Placeholder name matching depends on your data structure:
+
+**Dictionary keys (JSON) are case-sensitive:**
 
 **JSON:**
 ```json
@@ -435,6 +437,10 @@ Remember that placeholder names are case-sensitive:
 {{customername}}  → {{customername}} (not found!)
 ```
 
+**Note for developers:** If your data comes from code (not JSON files), property names may be case-insensitive depending on how the data is structured.
+
+**Best practice for template authors:** Always match the exact case used in your JSON keys to avoid confusion and ensure templates work reliably.
+
 ## Formatting Placeholders
 
 You can apply formatting to placeholders using format specifiers:

docs/for-template-authors/template-syntax.md

@@ -97,7 +97,7 @@ Second user: {{Users[1].Name}}, age {{Users[1].Age}}
 
 ### Case Sensitivity
 
-Placeholder names are **case-sensitive**. `{{Name}}` and `{{name}}` are different.
+JSON keys are **case-sensitive**. `{{Name}}` and `{{name}}` are different. Always match the exact case used in your JSON data.
 
 ---