fix: Search API to return all matching tags in matched_tags field

[aniketpalu]

What this PR does / why we need it:

1. Return all matching tags instead of just the first one

• Previously, when multiple tags matched a query, only one was returned
• Now all matching tags (both exact and fuzzy) are collected and returned

2. Changed matched_tag to matched_tags as a flat dictionary

• Before: "matched_tag": {"key": "value"} (single match)
• After: "matched_tags": {"key1": "value1", "key2": "value2"} (all matches)

3. Made matched_tags a mandatory field in all search results

• When query matches name/description, any matching tags are also returned
• When query is empty, all tags are included in matched_tags
• Empty {} when no tags match

Response Example for query = 'at'

{
  "query": "at",
  "projects_searched": [
    "test_project"
  ],
  "results": [
    {
      "type": "featureView",
      "name": "user_features",
      "description": "User demographic features",
      "project": "test_project",
      "matched_tags": {
        "team": "data"
      },
      "match_score": 100
    },
    {
      "type": "featureView",
      "name": "product_features",
      "description": "Product catalog features",
      "project": "test_project",
      "matched_tags": {},
      "match_score": 100
    },
    {
      "type": "featureView",
      "name": "transaction_features",
      "description": "Transaction payment features",
      "project": "test_project",
      "matched_tags": {},
      "match_score": 100
    },
    {
      "type": "featureView",
      "name": "user_on_demand_features",
      "description": "On-demand features combining user features with real-time data",
      "project": "test_project",
      "matched_tags": {
        "team": "data"
      },
      "match_score": 100
    },
    {
      "type": "feature",
      "name": "category",
      "description": "",
      "project": "test_project",
      "featureView": "product_features",
      "matched_tags": {},
      "match_score": 100
    },
    {
      "type": "savedDataset",
      "name": "user_training_dataset",
      "description": "",
      "project": "test_project",
      "matched_tags": {
        "team": "data"
      },
      "match_score": 100
    },
    {
      "type": "entity",
      "name": "user",
      "description": "User entity for customer data",
      "project": "test_project",
      "matched_tags": {
        "team": "data"
      },
      "match_score": 80
    },
    {
      "type": "entity",
      "name": "product",
      "description": "Product entity for catalog data",
      "project": "test_project",
      "matched_tags": {},
      "match_score": 80
    },
    {
      "type": "entity",
      "name": "transaction",
      "description": "Transaction entity for payment data",
      "project": "test_project",
      "matched_tags": {},
      "match_score": 80
    },
    {
      "type": "featureService",
      "name": "user_service",
      "description": "Service for user-related features",
      "project": "test_project",
      "matched_tags": {
        "team": "data"
      },
      "match_score": 80
    },
    {
      "type": "featureService",
      "name": "product_service",
      "description": "Service for product catalog features",
      "project": "test_project",
      "matched_tags": {},
      "match_score": 80
    }
  ],
  "pagination": {
    "page": 1,
    "limit": 50,
    "totalCount": 11,
    "totalPages": 1
  },
  "errors": []
}

Which issue(s) this PR fixes:

RHOAIENG-44611

Misc

[jyejare]

LGTM, but looks like tests are not really testing the multiple tags. Please add that.

[Srihari1192]

lgtm Thanks

[ntkathole]

Thanks