Introduce new mediator to define variables

[SanojPunchihewa]

Problem

Currently we need to use Synapse properties to define variables. However for a new user, using the property mediator and selecting the scopes to define a variable is not intuitive.

Proposed Solution

Introduce a new mediator called "Variable" with a new scope

• [x] Introduce new mediator to Synapse - Fixed with https://github.com/wso2/wso2-synapse/pull/2225
• [ ] Add option to export variables for Tracing
• [x] Add new simplified expression support - Fixed with https://github.com/wso2/wso2-synapse/pull/2233
• [ ] Update VSCode UISchema and serializer/deserializer

Alternatives

No response

Version

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