Add app menu extension spi

[pl-buiquang]

Signed-off-by: Paul Bui-Quang paul.buiquang@rte-france.com

Please check if the PR fulfills these requirements (please use '[x]' to check the checkboxes, or submit the PR and then click the checkboxes)

• [x] The commit message follows our guidelines
• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...) feature

What is the current behavior? (You can also link to an open issue here) Not able to extend the menu and display tab with custom content

What is the new behavior (if this is a feature change)? Extension service provider was added

[sonarcloud[bot]]

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0 Bugs
0 Vulnerabilities (and 0 Security Hotspots to review)
7 Code Smells

0.0% Coverage
0.0% Duplication