[FEATURE] Support Advanced Search

[BrocksiNet]

Description

We should test and explain how to integrate Advanced Search for Composable Frontends.

Use Case

Our customers are asking for that.

Proposed Solution

Please make sure to document the needed steps here.

Alternatives Considered

No response

Additional Context

You need to test it in a local environment with a commercial plugin activated (the feature is not in our cloud instance).

[mkucmus]

results after trying it out in comparison to storefront solution:
✅ adds meta-data to the response for completion (defined in actions, for example):

    "extensions": {
        "multiSuggestResult": {
            "apiAlias": "shopware_commercial_advanced_search_domain_suggest_multi_suggest_result"
        },
        "completionResult": {
            "apiAlias": "array_struct",
            "0": "frontends",
            "1": "composable-frontends"
        }
    },

❌ response does not contain information about categories - it works only for products
❌ does not handle 301 redirect for predefined actions (term defined in backend can lead to the external/internal pages)

The issue is blocked due to missing features for store-api that were mentioned above - the problem will be reported in the Commercial extension repository.