fix(search): missing schema and parsing for overrides

[sinedied]

Purpose

• Fixes the parsing of param overrides in the backend
• Add default param for ALLOWED_ORIGIN so that it's not asked on azd up

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Get the code

git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install