docs: enhance GCP integration documentation + add gcp wip ( workload identity )

[girish-cheedala]

• Revise GCP integration overview for clarity on discovery approaches and authentication methods.
• Introduce a detailed table of supported GCP services.
• Expand on enumeration scope with project-level and organization-level discovery options.
• Add warnings regarding permission requirements for organization-level enumeration.
• Include new authentication methods with descriptions and links.
• Add a new image for GCP integration screen.

[neo-by-projectdiscovery-dev]

Neo - PR Security Review

No security issues found

Highlights

• WIF attribute binding fix PRESERVED at line 1227 (attribute.sub/YOUR_TEAM_ID) - no regression
• Documentation restructuring with improved formatting and organization
• All security-critical configuration examples remain secure with proper placeholder values
• Zero scanner findings: 0 secrets, 0 Semgrep rules, 0 ast-grep patterns

Hardening Notes

• Changes since c2a09e7: 54 lines modified (34 insertions, 20 deletions) - purely documentation improvements
• No new gcloud commands, authentication methods, or security-relevant configuration introduced
• The incremental diff contains only formatting, structure, and clarity improvements to existing content

_{Comment @neo help for available commands. · Open in Neo}