[23757] Formatting the output

[zesk1999]

Description

Previously, topic data printed by Fast DDS Spy was heavily indented and multiline, making long arrays and nested objects verbose and harder to read at a glance.

Solution

This PR reformats the printed JSON to be more compact and readable by:

• Keeping arrays on a single line
• Retaining object indentation and valid JSON structure
• Avoiding unnecessary newlines to make payloads shorter and clearer

The change only affects output formatting, not the data content or serialization logic.

[Danipiza]

Just optimizing performance

[codecov]

Codecov Report

❌ Patch coverage is 0% with 45 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.46%. Comparing base (6dacfed) to head (07e7f63).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
fastddsspy_tool/src/cpp/tool/Controller.cpp	0.00%	45 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (6dacfed) and HEAD (07e7f63). Click for more details.

HEAD has 76 uploads less than BASE

Flag	BASE (6dacfed)	HEAD (07e7f63)
	77	1

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #135      +/-   ##
==========================================
- Coverage   60.71%   55.46%   -5.25%     
==========================================
  Files          27       26       -1     
  Lines        1718     1381     -337     
  Branches      706      530     -176     
==========================================
- Hits         1043      766     -277     
- Misses        299      317      +18     
+ Partials      376      298      -78     

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