fix for several input errors and a gemini function handling fix

[csells]

• Allow auto-focus overwrite on the LlmChatView for certain UX scenarios

• Strip trailing newlines out of speech-to-text output (it was just ugly)

• Allow provide your own speech-to-text implementation in case the built-in LLM-based solution is not cutting the mustard

• Fixed the function calling implementation to handle multiple tool calls. This gives the FirebaseProvider the inner loop to keep calling functions requested by Gemini until it gets all the info it needs to provide its response.

• Update edit canceling to reset the attachments and prompt.

issues fixed by this PR

• Avoiding autofocus #133
• [bug] stt should strip newlines #127
• Audio transcription returns mixed AI response or no text (iOS & Android) #100
• [bug] fix function calling to handle multiple tool calls #135
• [bug] canceling the editing of a prompt should reset the attachments and prompt #111

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• I listed at least one issue that this PR fixes in the description above.
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