feat(embedding): add litellm embeddings

[micpst]

This PR adds litellm embedding client and adds checks for litellm import errors.

[github-actions]

Trivy scanning results.

[github-actions]

Code Coverage Summary

Filename                                                  Stmts    Miss  Cover    Missing
------------------------------------------------------  -------  ------  -------  ----------------------------------------------------
dbally/_exceptions.py                                         1       0  100.00%
dbally/_main.py                                              12       0  100.00%
dbally/_types.py                                              8       1  87.50%   24
dbally/collection.py                                         93       1  98.92%   264
dbally/assistants/base.py                                    23       0  100.00%
dbally/assistants/openai.py                                  59       2  96.61%   59-76
dbally/audit/event_span.py                                    8       0  100.00%
dbally/audit/event_tracker.py                                34       6  82.35%   35, 48, 59, 69, 86, 92
dbally/audit/event_handlers/base.py                          15       0  100.00%
dbally/audit/event_handlers/cli_event_handler.py             48      33  31.25%   9-12, 38-39, 42-46, 56-58, 70-80, 99-106, 117-120
dbally/audit/event_handlers/langsmith_event_handler.py       29      25  13.79%   6-107
dbally/data_models/audit.py                                  28       0  100.00%
dbally/data_models/execution_result.py                       14       0  100.00%
dbally/embeddings/_exceptions.py                             15       6  60.00%   10-11, 20, 29-30, 39
dbally/embeddings/base.py                                     5       0  100.00%
dbally/embeddings/litellm.py                                 28      19  32.14%   7-8, 44-52, 69-85
dbally/iql/_exceptions.py                                    24       1  95.83%   33
dbally/iql/_processor.py                                     80       7  91.25%   16, 47, 64, 70, 76, 85, 91
dbally/iql/_query.py                                         13       1  92.31%   8
dbally/iql/_type_validators.py                               39       2  94.87%   24, 28
dbally/iql/syntax.py                                         36       9  75.00%   6-9, 27, 36, 60, 63-66
dbally/iql_generator/iql_generator.py                        31       0  100.00%
dbally/iql_generator/iql_prompt_template.py                  12       1  91.67%   38
dbally/llms/base.py                                          32       1  96.88%   35
dbally/llms/litellm.py                                       24      10  58.33%   8-9, 48-54, 61, 79
dbally/llms/clients/_exceptions.py                           15       6  60.00%   10-11, 20, 29-30, 39
dbally/llms/clients/base.py                                  24       2  91.67%   46-47
dbally/llms/clients/litellm.py                               44      20  54.55%   8-9, 65-71, 97-118
dbally/nl_responder/nl_responder.py                          29       4  86.21%   75-84
dbally/nl_responder/nl_responder_prompt_template.py           7       0  100.00%
dbally/nl_responder/query_explainer_prompt_template.py        7       0  100.00%
dbally/prompts/common_validation_utils.py                    15       0  100.00%
dbally/prompts/prompt_template.py                            28       2  92.86%   27, 35
dbally/similarity/chroma_store.py                            37       0  100.00%
dbally/similarity/detector.py                                73       6  91.78%   21, 200-204
dbally/similarity/faiss_store.py                             38      35  7.90%    5-103
dbally/similarity/fetcher.py                                  5       0  100.00%
dbally/similarity/index.py                                   26       0  100.00%
dbally/similarity/sqlalchemy_base.py                         44      23  47.73%   17, 35-37, 46, 57-59, 68, 77, 86-89, 99-105, 123-126
dbally/similarity/store.py                                    7       0  100.00%
dbally/utils/errors.py                                        2       0  100.00%
dbally/view_selection/base.py                                 7       0  100.00%
dbally/view_selection/llm_view_selector.py                   20       0  100.00%
dbally/view_selection/random_view_selector.py                10      10  0.00%    1-35
dbally/view_selection/view_selector_prompt_template.py       11       2  81.82%   32-33
dbally/views/base.py                                          9       0  100.00%
dbally/views/decorators.py                                    6       0  100.00%
dbally/views/exposed_functions.py                            33       1  96.97%   24
dbally/views/methods_base.py                                 34       2  94.12%   75, 83
dbally/views/pandas_base.py                                  33       1  96.97%   64
dbally/views/sqlalchemy_base.py                              37       7  81.08%   48, 63-65, 83-87
dbally/views/structured.py                                   35       0  100.00%
dbally/views/freeform/text2sql/_autodiscovery.py            113      18  84.07%   107-108, 272, 275, 288-300, 304, 319-321, 333-334
dbally/views/freeform/text2sql/_config.py                    20       0  100.00%
dbally/views/freeform/text2sql/_errors.py                     6       3  50.00%   10-12
dbally/views/freeform/text2sql/_view.py                      49       6  87.76%   85, 89-92, 95
dbally_cli/main.py                                            5       5  0.00%    1-11
dbally_cli/similarity.py                                     21       0  100.00%
TOTAL                                                      1561     278  82.19%

Diff against main

Filename                            Stmts    Miss  Cover
--------------------------------  -------  ------  --------
dbally/embeddings/_exceptions.py      +15      +6  +60.00%
dbally/embeddings/base.py              +5       0  +100.00%
dbally/embeddings/litellm.py          +28     +19  +32.14%
dbally/llms/litellm.py                 +6      +4  -8.34%
dbally/llms/clients/litellm.py         +5      +4  -4.42%
TOTAL                                 +59     +33  -0.84%

Results for commit: 6962c3f

Minimum allowed coverage is 60%

♻️ This comment has been updated with latest results

[mhordynski]

lgtm