Fix multi-line function parsing in dependency analyzer

[cherotuga]

Improve the .parse_function() function to better handle function calls that span multiple lines with arguments. The previous implementation used deparse() which was problematic for multi-line function calls.

Changes:

• Add explicit handling for function calls with is.call(x) && length(x) >= 1
• Capture function names and recursively parse arguments to find nested calls
• Add proper symbol handling with is.symbol(x)
• Remove problematic deparse() fallback that couldn't handle multi-line calls
• Filter out empty results with out[nzchar(out)]
• Add length check for safety in $ operator handling

This allows the project visualizer to correctly identify dependencies in functions with complex multi-line argument structures.

🤖 Generated with Claude Code

[codecov]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
R/project_visualiser.R	0.00%	12 Missing ⚠️

📢 Thoughts on this report? Let us know!