docs: comprehensive documentation and examples overhaul

[aeswibon]

Description

This PR transitions GitOpsCTL into a developer-friendly ecosystem by implementing comprehensive technical documentation, detailed feature guides, and production-grade examples.

Fixes #35

Type of change

• Documentation update
• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Verified all documentation links in the IDE and via local preview.
• Tested the 'Quick Demo' workflow using the new examples.
• Ran scripts/cli-smoke.sh to ensure no regressions in CLI behavior.
• Fixed a nil pointer dereference in the reconciliation loop discovered during documentation testing.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Local pre-commit checks pass successfully