Collapse messages with excessive newlines regardless of character count

[Vishvendra47]

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  • Virtual device (emulator), Android 15
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Description

Previously, whether a message needed a "Read more" overflow was decided purely by character count (MAX_BODY_DISPLAY_LENGTH). Messages with very few characters but a large number of newlines were never flagged as overflowing, causing them to render at full height and degrade scroll performance (see #14861).

This adds a line-count check (MAX_BODY_DISPLAY_LINES) alongside the existing character-count check in hasExtraText(), and introduces getMaxBodyDisplayLength() to compute the correct truncation point based on whichever limit (characters or lines) is hit first.

How I tested it:

• Built the project and ran it on a virtual device (Android 15).
• Sent a message consisting of a short string with a large number of newlines (e.g. a single character, followed by many blank lines, followed by another character) and confirmed it now correctly collapses with a "Read more" option, and that scrolling near it is smooth.
• Verified that existing behavior for normal long text messages (1000+ characters, few/no newlines) still collapses correctly as before, confirming no regression.

Fixes #14861