chore(cursor): add commit and spelling rules

Made-with: Cursor

.cursor/rules/commit.mdc

@@ -0,0 +1,26 @@
+---
+description: Git commit messages and how to split work into commits
+alwaysApply: true
+---
+
+# Commits
+
+When preparing commits (especially when the user asks to commit):
+
+1. **Prefer multiple commits** over one large commit when changes span distinct concerns (e.g. UI vs docs vs API). One logical unit per commit.
+2. **Message format:** `type(scope): short imperative subject` (lowercase subject after the colon; no trailing period).
+   - **Types:** `feat`, `fix`, `docs`, `style`, `refactor`, `test`, `chore`, `perf` (use what fits).
+   - **Scope:** optional but encouraged — e.g. `ui`, `api`, `profiles`, `presets`, `esp32`.
+3. **Subject line:** ~50 characters or less; describe *what* changed, not the ticket number alone.
+4. **Body:** only when needed (breaking change, non-obvious rationale, or multiple bullets). Otherwise subject is enough.
+
+**Examples**
+
+- `feat(ui): gate profile delete to edit mode`
+- `docs: document run vs edit in API`
+- `fix(api): resolve preset delete route argument clash`
+
+**Do not**
+
+- Squash unrelated fixes and doc tweaks into one commit unless the user explicitly wants a single commit.
+- Use vague messages like `update`, `fixes`, or `wip`.