detect when user is talking and send data channel message

[mahibi]

resolve #88

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not needed
• 🔖 Capability is checked or not needed
• 🔙 Backport requests are created or not needed: /backport to stable-xx.x
• 📅 Milestone is set
• 🌸 PR title is meaningful (if it should be in the changelog: is it meaningful to users?)

[mahibi]

/backport to stable-17.1

[AndyScherzinger]

LGTM, just an additional lint warning

[github-actions]

Codacy

Lint

Type	master	PR
Warnings	94	93
Errors	0	0

SpotBugs

Category	Base	New
Correctness	9	9
Dodgy code	123	123
Internationalization	5	5
Malicious code vulnerability	3	3
Performance	8	8
Security	2	2
Total	150	150

[github-actions]

APK file: https://www.kaminsky.me/nc-dev/android-artifacts/3298-talk.apk



To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud Talk app.

[backportbot-nextcloud]

The backport to stable-17.1 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable-17.1
git pull origin stable-17.1

# Create the new backport branch
git checkout -b fix/foo-stable-17.1

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts. Resolve them.
git cherry-pick abc123

# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable-17.1

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport

[AndyScherzinger]

/backport to stable-17.1

[backportbot-nextcloud]

The backport to stable-17.1 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable-17.1
git pull origin stable-17.1

# Create the new backport branch
git checkout -b fix/foo-stable-17.1

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts. Resolve them.
git cherry-pick abc123

# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable-17.1

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport