Initial commit of current state

spoken_text.py

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+"""Strip formatting that only makes sense on a screen, before it is spoken.
+
+`VOICE_STYLE` asks Claude not to emit markdown, and mostly he doesn't — but
+asking is probabilistic and hearing "asterisk asterisk aloud asterisk asterisk"
+once is enough. This is the deterministic half.
+
+Pipecat's `MarkdownTextFilter` does most of it and runs *after* sentence
+aggregation, so formatting split across streaming chunks is already reassembled
+by the time it sees the text. What it leaves behind, measured:
+
+    'Use ~~strike~~'      -> 'Use ~~strike~~'      still spoken as tildes
+    '- first bullet'      -> '- first bullet'      spoken as "dash"
+    'the sample_rate is'  -> 'the sample_rate is'  spoken as "underscore"
+    'Multiply 3 * 4'      -> 'Multiply 3  4'       the "times" is lost
+
+so this subclass handles those four and tidies the spacing.
+"""
+
+import re
+
+from pipecat.utils.text.markdown_text_filter import MarkdownTextFilter
+
+# Run before the markdown filter, which would otherwise eat the asterisk.
+_TIMES = re.compile(r"(?<=\d)\s*\*\s*(?=\d)")
+
+_STRIKETHROUGH = re.compile(r"~~(.+?)~~")
+# Only at the start of a line, so a hyphenated word is untouched.
+_LIST_MARKER = re.compile(r"^[ \t]*[-*•]\s+", re.MULTILINE)
+# Identifiers read better as words: "sample_rate" -> "sample rate".
+_UNDERSCORE_WORD = re.compile(r"(?<=\w)_(?=\w)")
+_EXTRA_SPACE = re.compile(r"[ \t]{2,}")
+
+
+class SpokenTextFilter(MarkdownTextFilter):
+    """Markdown filtering, plus the leftovers that matter when read aloud."""
+
+    async def filter(self, text: str) -> str:
+        text = _TIMES.sub(" times ", text)
+        text = await super().filter(text)
+        text = _STRIKETHROUGH.sub(r"\1", text)
+        text = _LIST_MARKER.sub("", text)
+        text = _UNDERSCORE_WORD.sub(" ", text)
+        return _EXTRA_SPACE.sub(" ", text)