Support for Expert Assistant inline action links

[Steve-Mcl]

Description

This pull request adds support for assistant action links in the immersive editor context.

Assistant action link handling:

• Added logic in AnswerWrapper.vue to detect and handle clicks on assistant action links in the immersive editor, parsing parameters and dispatching the invokeAction Vuex action only for supported actions. [1] [2] [3]
• Introduced the invokeAction action in the assistant Vuex module to facilitate action invocation via messaging.

Sanitization and link identification:

• Enhanced the sanitize function in String.js to recognize and preserve custom assistant action links (nr-assistant://), adding data attributes for action and parameters, and preventing unsafe modifications. [1] [2]
• Updated RichContent.vue to pass supportedActions to sanitize, enabling proper identification of action links during content rendering. [1] [2]
• Connected supportedActions state to components to ensure only valid actions are processed and rendered. [1] [2]

These changes collectively enable secure, context-aware assistant action invocation from answer content in the immersive editor, while maintaining robust sanitization and validation of action links.

Related Issue(s)

closes #6816

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.62%. Comparing base (b8758ac) to head (870f924).
⚠️ Report is 12 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6864   +/-   ##
=======================================
  Coverage   76.62%   76.62%           
=======================================
  Files         399      399           
  Lines       20165    20165           
  Branches     4856     4856           
=======================================
  Hits        15452    15452           
  Misses       4713     4713           

Flag	Coverage Δ
backend	76.62% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[Steve-Mcl]

@cstns I have merged all, updated & answered your query on the review - GTG?

[cstns]

yes, gtg! marked my comment as resolved