chore(DuoChat): refactor context items to use standard properties
What does this MR do?
Refactors the Duo Chat context item components to use a standard set of item properties.
The aim is to move all the mapping of data out of these UI components, and the specific handling fo different category types. This will make these UI components more data-driven, and allow us to add new context categories in the language server without needing matching changes in the UI project.
The main changes are outlined on the issue here: #2907 (comment 2170161687)
Screenshots or screen recordings
There is a slight user-facing change introduced by using the same property in two places - we now show the project path in search items for file, issue and merge_request categories. Overview of context items:
| category | search items | popover | 
|---|---|---|
| file |   |   | 
| local_git |   |   | 
| issue |   |   | 
| MR |   |   | 
Integration merge requests
This change is backwards compatible - new properties are used if they exist, otherwise falls back to the existing properties.
A future MR will remove the old properties: !4718 (closed)
Does this MR meet the acceptance criteria?
This checklist encourages the authors, reviewers, and maintainers of merge requests (MRs) to confirm changes were analyzed for conformity with the project's guidelines, security and accessibility.
Toggle the acceptance checklist
Conformity
- 
Code review guidelines. 
- 
GitLab UI's contributing guidelines. 
- 
If it changes a Pajamas-compliant component's look & feel, the MR has been reviewed by a UX designer. 
- 
If it changes GitLab UI's documentation guidelines, the MR has been reviewed by a Technical Writer. 
- 
If the MR changes a component's API, integration MR(s) have been opened (see integration merge requests above). 
- 
Added the ~"component:*"label(s) if applicable.
Security
If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:
- 
Label as security and @ mention @gitlab-com/gl-security/appsec
- 
Security reports checked/validated by a reviewer from the AppSec team 
Accessibility
If this MR adds or modifies a component, take a few moments to review the following:
- 
All actions and functionality can be done with a keyboard. 
- 
Links, buttons, and controls have a visible focus state. 
- 
All content is presented in text or with a text equivalent. For example, alt text for SVG, or aria-labelfor icons that have meaning or perform actions.
- 
Changes in a component’s state are announced by a screen reader. For example, changing aria-expanded="false"toaria-expanded="true"when an accordion is expanded.
- 
Color combinations have sufficient contrast. 
Closes #2907 (closed)