[amanKG777]

This adds a few system voice commands to Backtalk, so you can change common phone settings and hear device status without leaving what you're doing.

Say "turn on Do Not Disturb" or "turn off dnd" to switch Do Not Disturb. The first time, Backtalk says it needs Do Not Disturb access and opens Android's setting for it. "Volume up" and "volume down" change the media volume and say the new level as a percentage, and "mute" and "unmute" mute and unmute it. "Battery" says the battery level and charging state, and "status" says what the status bar shows. "Open settings" opens Android Settings, and "open Backtalk settings" opens Backtalk's. "Find [name]", also "focus", "locate" and "search for", moves focus to the control on screen that best matches the name, and says what it found, or that it found nothing.

Do Not Disturb uses the notification policy API. Wi-Fi, hotspot, mobile data and Bluetooth aren't included, because Android has no supported way for an app to switch them. Turning Do Not Disturb off is decided by the word "off" or "disable" in what you said, since the "on" and "off" phrases are close enough that a fuzzy match alone finds both. If a phrase has both words, or neither and is unclear, Backtalk does nothing instead of guessing.

As with the calling commands, there is no switch: they only run when you say them after the voice command gesture. The new behaviour is described in differences.md.

Tested on a POCO M7 5G with Android 16, using Google's speech recognition service. I tried every command on the phone: Do Not Disturb on and off, volume up and down, mute and unmute, battery, status, open settings, open Backtalk settings, and find, both with a control that is on screen and with one that isn't. The first pass found three mistakes ("unmute" muted, "status" read only the battery, and "open Backtalk settings" opened Android Settings), which are fixed and described in my comment below, and I then tried them again. testPhoneDebugUnitTest, :lintPhoneDebug and :lintWearDebug all pass.

[trypsynth]

Could you try volume, mute, battery, status, open settings and find on a device, and say how they went? Only Do Not Disturb has been tried so far.

[amanKG777]

I tried the commands you asked about on a POCO M7 5G with Android 16, using Google's speech recognition service. Most worked, and I found three mistakes, which I've fixed in the new commit.

What worked at first: "volume up" and "volume down" change the volume and say the new level. "Mute" mutes. "Battery" says the battery status. "Open settings" opens Android Settings. "Find" with a button's name moves focus to it, and "find" with something that isn't on screen says so. "Turn off do not disturb" works.

What was wrong:

• "Unmute" kept muting. The matcher found "mute" inside "unmute", and the mute check ran first.
• "Status" said only the battery, not the time and network. "Battery status" contains "status", so the battery check took it.
• "Open Backtalk settings" opened Android Settings, while "open talkback settings" opened Backtalk's. The speech recognizer writes "Backtalk" as "back talk", and the Android Settings check matched any sentence that contained "settings".

These commands now match whole phrases and not words found inside a sentence, "unmute" is checked as a whole word, and "back talk" is read as "Backtalk". I added SystemCommandPhrasesTest for these cases.

After the fix I tried "mute" then "unmute", "status", "battery", "open settings" and "open Backtalk settings" again on the phone, and all of them did the right thing. testPhoneDebugUnitTest, :lintPhoneDebug and :lintWearDebug pass.