Improvise search in open conversations

[sowjanyakch]

follow up to #4497

see comment #4497 (review)

1. Improvise search in open conversations.
2. Search edit text should occupy a single line.

🚧 TODO

• ...

🏁 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?)

[github-actions]

APK file: https://www.kaminsky.me/nc-dev/android-artifacts/4559-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.

[github-actions]

Codacy

Lint

Type	master	PR
Warnings	158	158
Errors	71	71

SpotBugs

Category	Base	New
Bad practice	6	6
Correctness	16	16
Dodgy code	71	71
Internationalization	3	3
Malicious code vulnerability	3	3
Performance	4	4
Security	1	1
Total	104	104