Address Copilot review comments on text positioning PR

[boardtc]

Follow up on the Copilot review comments raised on upstream PR burhanrashid52#592.

Scope:

• fix RTL consistency for explicit text placement coordinates
• make the tap-capture overlay non-focusable / excluded from accessibility
• correct the README Java example for Position
• clarify PhotoEditor overload KDoc so the default interface fallback behavior is documented

After fixing:

• commit against the existing PR branch
• update the upstream PR with the fixing commit
• add a follow-up note on upstream issue Allow positioning text on image (currently fixed to center and may overlap content) burhanrashid52/PhotoEditor#589

[boardtc]

Addressed in commit 0c31132.

What changed:

• switched explicit placement to ALIGN_PARENT_LEFT to keep top-left coordinates consistent in RTL
• made the tap-capture overlay non-focusable and excluded it from accessibility traversal
• corrected the README Java example to use new Position(...)
• clarified the PhotoEditor overload KDoc about the default fallback behavior