docs: Add documentation pages for new evaluation components

[julian-risch]

We need to add documentation pages for the new evaluation components:

• docs: Add documentation page about AnswerExactMatchEvaluator #7472
• docs: Add documentation page about DocumentMAPEvaluator #7473
• docs: Add documentation page about DocumentMRREvaluator #7474
• docs: Add documentation page about DocumentRecallEvaluator #7475
• docs: Add documentation page about FaithfulnessEvaluator #7476
• docs: Add documentation page about LLMEvaluator #7477
• docs: Add documentation page about SASEvaluator #7478

ContextRelevanceEvaluator will be added soon too but there is no PR for it yet. #7025

[julian-risch]

all done