Tooltip width and placement fine-tuning

[aldefy]

Problem

Tooltip width defaults to screen-width minus margins. No way to:

• Set a specific max width
• Control horizontal alignment relative to the cutout (leading edge, centered, trailing edge)
• Set custom margins per-target

This makes it hard to achieve tight, compact tooltip compositions that match design specs.

Proposed Solution

Add to CoachmarkConfig or CoachmarkTarget:

CoachmarkTarget(
    id = "target",
    tooltipMaxWidth = 280.dp,          // Cap tooltip width
    tooltipAlignment = TooltipAlignment.LEADING_EDGE, // Align to cutout's leading edge
    tooltipMargin = PaddingValues(horizontal = 24.dp),
)

Context

Client feedback: tooltip feels disconnected from cutout. Figma shows a compact tooltip close to the target, but the app renders a wide tooltip far below.