chore: import upstream snapshot with attribution

docs/source/tools/intro.rst

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+:orphan:
+
+Speech AI Tools
+===============
+
+NeMo provides a set of tools useful for developing Automatic Speech Recognitions (ASR) and Text-to-Speech (TTS) synthesis models: \
+`https://github.com/NVIDIA/NeMo/tree/stable/tools <https://github.com/NVIDIA/NeMo/tree/stable/tools>`__ .
+
+.. toctree::
+   :maxdepth: 1
+
+   nemo_forced_aligner
+   ctc_segmentation
+   speech_data_explorer
+   comparison_tool
+   asr_evaluator
+
+
+There are also additional NeMo-related tools hosted in separate github repositories:
+
+.. toctree::
+   :maxdepth: 1
+
+   speech_data_processor