[Backport main] Added Multimodal semantic search feature

[martin-gaievski]

Upport Multimodal search support (#359) from 2.x 841f280 to main

Check List

• All tests pass
• Commits are signed as per the DCO using --signoff

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[codecov]

Codecov Report

Merging #434 (60c4f69) into main (0f73cc6) will decrease coverage by 0.20%.
The diff coverage is 82.66%.

❗ Current head 60c4f69 differs from pull request most recent head 801327d. Consider uploading reports for the commit 801327d to get more accurate results

@@             Coverage Diff              @@
##               main     #434      +/-   ##
============================================
- Coverage     84.56%   84.37%   -0.20%     
- Complexity      449      498      +49     
============================================
  Files            38       40       +2     
  Lines          1348     1491     +143     
  Branches        201      228      +27     
============================================
+ Hits           1140     1258     +118     
- Misses          120      133      +13     
- Partials         88      100      +12     

Files	Coverage Δ
...g/opensearch/neuralsearch/plugin/NeuralSearch.java	72.72% <100.00%> (+1.29%)	⬆️
...pensearch/neuralsearch/processor/NLPProcessor.java	92.71% <100.00%> (ø)
...ocessor/factory/TextEmbeddingProcessorFactory.java	100.00% <100.00%> (ø)
...or/factory/TextImageEmbeddingProcessorFactory.java	100.00% <100.00%> (ø)
...earch/neuralsearch/ml/MLCommonsClientAccessor.java	94.28% <93.10%> (-0.59%)	⬇️
...nsearch/neuralsearch/query/NeuralQueryBuilder.java	88.88% <83.33%> (ø)
...lsearch/processor/TextImageEmbeddingProcessor.java	78.43% <78.43%> (ø)