fix(config_guide): correct CEL and variables docs against codebase

[emjay0921]

Why is this change needed?

QA review found 14 inaccuracies in the CEL and variables documentation when verified against the OpenSPP2 codebase.

How was the change implemented?

• Fixed expression states: Draft → Active → Inactive (was Draft → Pending Approval → Published → Archived)
• Fixed menu path: Studio → Logic Design (was Studio → Rules)
• Removed non-existent functions: startswith(), contains(), before(), after()
• Removed Events as aggregate target (only members, enrollments, entitlements exist)
• Rewrote event aggregate sections to use Computed (CEL) with event functions
• Removed undocumented where parameter and Python fallback references
• Clarified collection predicate syntax note
• Replaced raw Odoo model names in profiles table
• Renamed "Variables & Indicators" to "Variables"

Related links

https://projects.acn.fr/projects/acn-eng/work_packages/823

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[gemini-code-assist]

Code Review

This pull request updates the OpenSPP documentation to reflect workflow changes, including renaming 'publishing' to 'activating' and updating menu navigation. It also transitions event data access from aggregate targets to dedicated CEL functions and simplifies string function recommendations. A review comment correctly identifies a need to remove the 'events' relation from the syntax guide's relations table to maintain consistency with these architectural changes.

[gemini-code-assist]

The events relation should be removed from the 'Available Relations' column to maintain consistency with the rest of the documentation changes. The PR description and other updated files (e.g., variables.md, variable_types.md) state that event data is no longer an aggregate target and should be accessed via dedicated event functions instead of collection relations.

Suggested change

	| `registry_individuals` | Individual registrant | `groups`, `enrollments`, `entitlements`, `events` |
	| `registry_groups` | Group/household | `members`, `enrollments`, `entitlements`, `events` |
	| registry_individuals | Individual registrant | groups, enrollments, entitlements |
	| registry_groups | Group/household | members, enrollments, entitlements |