Apply restrictions programatically to search sources

[pelord]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines:https://github.com/infra-geo-ouverte/igo2/blob/master/.github/CONTRIBUTING.md#git-commit-guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What is the current behavior? (You can also link to an open issue here)
When a search is triggered programmatically, there is no way to control which source is used.
The hashtag has been tested but not interesting because hashtag is linked to search result.

What is the new behavior?
adding an option property the filter the sources BEFORE the call.

2 properties added to TextSearchOptions interface

  searchType?: 'Feature' | 'Layer'; // refer to search.enum.ts SEARCH_TYPES = [FEATURE, LAYER];
  getEnabledOnly?: boolean;

searchType refer the the search source type
getEnabledOnly is to bypass or not the user's defined enabled sources.

Use fce7278 as an example.

Does this PR introduce a breaking change? (check one with "x")

[ ] Yes
[x] No

If this PR contains a breaking change, please describe the impact and migration path for existing applications:

Other information: