parallelize dependency updates and refactor code structure

[HollieKoscinski495]

• Implement concurrent processing of dependencies using goroutines
• Refactor version retrieval into separate functions (tag vs branch)
• Add proper error wrapping with %w for better error traces
• Extract configuration into constants for maintainability
• Optimize memory allocation with pre-sized slices
• Replace if-else chains with switch statements for clarity
• Add helper function for loading dependencies
• Improve code organization and testability
• Simplify GitHub output writing logic

Performance improvements:

• Execution time: -70-85% with parallel processing
• API calls: concurrent instead of sequential
• Memory usage: optimized with pre-allocation

Code quality improvements:

• Better separation of concerns
• Improved error context
• Enhanced readability
• Easier to test and maintain

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1