[Skill idea] flutter-create-bottom-sheet-flow — scaffold a typed-result bottom sheet

## Environment

- **Language model:** Claude Opus 4.7
- **Agent harness:** Claude Code
- **Project type:** Production Flutter app

## Problem

Bottom sheets are one of the most common UX patterns in production Flutter apps, and one of the most frequently misimplemented:

- Wrong route type (`MaterialPageRoute` instead of a transparent route)
- Missing typed result on close (forcing callers to `dynamic`-cast)
- Height management mistakes (`fitToContent` vs `heightFactor`, max-height clamping)
- `isDismissible` / `enableDrag` / `useSafeArea` defaults inconsistent across the app

The current Navigation/Routing roadmap has `flutter-implement-imperative-navigation` (P1) and `flutter-setup-declarative-routing` (published), but **no skill addresses the bottom-sheet flow specifically**.

## Proposed skill

**Name:** `flutter-create-bottom-sheet-flow`

**Description (draft):**
> Scaffold a bottom sheet route with typed `pop` result, height management (`fitToContent` vs fractional height), and dismissible/drag configuration. Use when adding a modal flow that returns data to its caller, such as a confirmation, picker, or detail panel.

**Decisions the skill captures:**
- Typed `Result` class vs nullable return
- `fitToContent` (max 70% height recommended) vs fixed `heightFactor`
- `isDismissible` + `enableDrag` policy
- Caller-side wiring (how the parent ViewModel triggers and consumes the result)

## Why a dedicated skill

Bottom sheets sit at the intersection of routing + UI + state contract. A general "navigation" skill won't cover the result-typing and height-management decisions specific to sheets. Doing it as a separate skill keeps both skills small and focused.

## Real-world reference

We maintain this as an internal skill and it eliminated a recurring class of "sheet pops `dynamic`, caller crashes" bugs. Happy to share the template structure.

## Roadmap fit

Sits in the **Navigation and Routing** category alongside `flutter-implement-imperative-navigation`.