Add missing strings and update strings.xml

[tmpjx555]

Add missing and update strings

Description

Please describe the changes in this Pull Request, what problem they solve, and the motivation behind them.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring / Code Condensing / Performance optimization
• Documentation update

Core Security & Architecture Verification

As a security-first repository under secure phone apps, please confirm the following:

• No Internet Permission: This PR does not introduce any internet connectivity, API calls, or remote tracker dependency.
• Native Components Only: This PR leverages native Android framework utilities (TelecomManager, ContactsContract, standard Room / Jetpack Compose) without pulling in high-overhead or untrusted third-party libraries.
• No Telemetry: No third-party analytics or tracker SDKs have been added.

Testing & Verification

• Compiled successfully with ./gradlew compileDebugSources or gradle :app:assembleDebug.
• Tested on a physical device / emulator (please specify Android version: ______).
• Verified that permission handling is dynamic and doesn't crash the app.

Screenshots (if applicable)

Please provide before/after screenshots for any user-interface changes.