feat(RND-104): add support for loading color preset from json

[asvishnyakov]

Description

This PR adds support for loading color presets from JSON.

1. Presets defined in the theme will still be embedded into the bundle and used at runtime, so no additional requests are added for existing presets.
2. If the frontend can't find a color preset with the specified name, it will try to load it from a JSON file in the assets/presets folder. The folder name can be changed upon request if needed.

Fallback logic has changed after AI review:

Before:

1. Try get preset
2. Fallback to default
   a. Dead code lead to missed attempt to use current preset from settings
   b. This is probably a bug. Try to define non-existing preset in white labeling and then see theme falling back to default preset instead of the one specified in current field of settings_data.json

After:

1. Try get preset
2. Fallback to current
3. Fallback to default

References

Jira-link:

Artifact URL:

https://vc3prerelease.blob.core.windows.net/packages/vc-theme-b2b-vue-2.37.0-pr-2100-c9d0-c9d02f4f.zip

[Copilot]

Pull request overview

This PR adds support for dynamically loading color presets from JSON files stored in the /assets/presets directory, providing flexibility for runtime theme customization without requiring bundle rebuilds.

Key Changes:

• Made addPresetToThemeContext and getPreset functions asynchronous to support fetching presets from external files
• Implemented a three-tier loading strategy: bundled presets → runtime cache → fetch from /assets/presets → fallback to default
• Added runtime caching via dynamicPresetsCache Map to avoid redundant network requests

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 7 comments.

File	Description
client-app/core/composables/useThemeContext.ts	Implements async preset loading with fetch API, adds caching mechanism, and provides fallback logic to default preset
client-app/app-runner.ts	Updates preset loading call to properly await the now-async addPresetToThemeContext function

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

client-app/core/composables/useThemeContext.ts:100

• The nullish coalescing assignment on line 94 already ensures preset will never be null after this line. The subsequent if-else block checking if preset exists (lines 96-100) is redundant since preset will always be truthy after line 94. Consider removing the else block and the conditional check, or restructuring the logic for clarity.

    preset ??= presets.default;

    if (preset) {
      themeContext.value.preset = preset;
    } else {
      throw new Error("Missing preset");
    }

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[asvishnyakov]

@copilot You first overview outdated, update it

[Copilot]

@asvishnyakov I've opened a new pull request, #2102, to work on those changes. Once the pull request is ready, I'll request review from you.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[asvishnyakov]

Please ignore Copilot overview - it's outdated and Copilot is stupid enough to not being able update it