Docs: Add context to BCell authorization examples

[kluth]

Problem

BCell authorization examples lack context about role assignment and permission storage.

Affected Files

Documentation: /home/matthias/projects/synapse/docs/systems/immune/README.md (lines 375-408)

Issue Details

Severity: LOW
Impact: May cause confusion during implementation

Current Example

const result = await authz.authorize({
  userId: 'user-123',  // How does BCell know user-123's permissions?
  resource: 'posts',   // What format should this be?
  action: 'create',    // What actions are valid?
});

Missing Context

1. How does BCell store and retrieve user roles?
2. What's the expected format of resource and action strings?
3. What happens if user has no roles assigned?
4. Where are role-permission mappings stored?
5. Can you query a user's current roles?

Recommended Enhancement

Add explanation sections:

• Role assignment and storage mechanism
• Resource/action naming conventions
• Permission lookup process
• Error handling for missing roles
• Role query methods

Priority

LOW - Contextual enhancement for better understanding

References

• Documentation Issue Log: /home/matthias/projects/synapse/DOCUMENTATION_ISSUE_LOG.md (Issue Claude/setup framework from readme 011 c ur h7 vu usiyb7oe mdod1 j #12)
• Documentation Fixes Needed: /home/matthias/projects/synapse/DOCUMENTATION_FIXES_NEEDED.md (FIX-12)

User Story

As a developer implementing authorization, I want to understand how BCell stores and retrieves permissions, so that I can properly set up and query the authorization system.

Acceptance Criteria

• Explain role storage mechanism
• Document resource/action format conventions
• Add role query examples
• Document error conditions
• Include persistence considerations