fix: refresh IME analysis on selection changes

[zefutoff]

Refresh Grammalecte IME analysis when the editor selection changes while the IME is already open.

This fixes editors where the user switches to Grammalecte before selecting the text to correct.

Changes:

• handle Android selection updates in the IME;
• debounce selection refreshes;
• invalidate stale analyses when the selection becomes empty;
• extend the real InputConnection instrumentation test to cover late selection;
• update testing documentation and changelog.

Validated locally with:

• make check
• make assemble
• full :app:connectedDebugAndroidTest
• Samsung Galaxy S21 / Android 15
• Proton Mail late-selection workflow