app: add icon-only verse copy selection

[nehemiaharchives]

What changed

• Added a structural Bible text selection model for the reader.
• Added long-press verse selection in Single, Bilingual Side, and Bilingual Under reading modes.
• Added an icon-only floating popup using the existing content_copy and select_all compose resources.
• Copy action writes the selected Bible text to the clipboard.
• Select-all action expands the current selection to the full chapter.
• Bilingual long-press initially selects only the main translation verse; full-chapter selection includes main/sub translation units in reading order.

UX intent

This keeps the reader surface non-selectable by default. It does not enable generic text selection or a text-label context menu; the interaction stays Bible-structured and icon-only.

Validation

Could not run Gradle checks in this environment because the shell has no GitHub/network access and gh is not installed. I inspected the changed Kotlin files through the GitHub connector after writing them.