Fixes #140

What was changed?

• Improved Preview Modal behavior to close when pressing the Escape key and display API error messages.
• Enhanced Section Input Handling to support non-sequential inputs (e.g., 1,3,5) and correctly interpret range formats (e.g., 1-5).

Why was it changed?

• Modal Usability Issues: Previously, the preview modal did not close with the Escape key, forcing users to click manually. Additionally, API error messages were not displayed, making troubleshooting difficult.
• Section Input Limitations: The system only handled sequential inputs, making it inconvenient for users who wanted to specify non-sequential sections or use range-based inputs.

How was it changed?

1. file_search_operations.py

• Extracts section numbers correctly, even for non-sequential and range inputs.
• Ensures valid sections are processed by checking against the total number of sections (if section_number > len(specify_lines): continue).
• Handles missing section numbers gracefully by verifying start_line before using it.

2. OrcaDashboardComponent.js

• Added a keydown event listener inside useEffect to close the preview modal when Escape is pressed.
• The function handleNumSectionsBlur was modified to parse non-sequential section inputs and expand range inputs (e.g., 1-5 to 1,2,3,4,5). Uses Set() to store unique values and avoid duplicates. Splits input by ,, processes ranges (x-y), and converts valid numbers into an array. Finally, sorts the parsed values and updates the state.