feat: single-click text inputs to edit, drag/resize on shape body

Shapes are now grabbable/draggable/resizable on first click (body or
handles), editable on double-click, but clicking directly on a text
input (textarea, contenteditable, text input) immediately enters edit
mode and focuses the input — no double-click required.

Works by hit-testing text inputs at pointer coordinates before
initiating drag, checking both light DOM and shadow DOM of slotted
content.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/folk-shape.ts

@@ -340,6 +340,36 @@ export class FolkShape extends FolkElement {
 		this.dispatchEvent(new CustomEvent("edit-enter"));
 	}
 
+	/** Check if a screen-space point overlaps a text input inside this shape's slotted content. */
+	#findTextInputAtPoint(clientX: number, clientY: number): HTMLElement | null {
+		const slot = (this.renderRoot as ShadowRoot).querySelector("slot");
+		if (!slot) return null;
+
+		const TEXT_SELECTOR = 'textarea, [contenteditable="true"], input:not([type="checkbox"]):not([type="radio"]):not([type="range"]):not([type="button"]):not([type="submit"]):not([type="reset"]):not([type="hidden"])';
+
+		for (const el of slot.assignedElements()) {
+			// Check light DOM children
+			const lightInputs = el.querySelectorAll<HTMLElement>(TEXT_SELECTOR);
+			for (const input of lightInputs) {
+				const rect = input.getBoundingClientRect();
+				if (clientX >= rect.left && clientX <= rect.right && clientY >= rect.top && clientY <= rect.bottom) {
+					return input;
+				}
+			}
+			// Check shadow DOM children (one level deep — covers all folk-* shapes)
+			if ((el as Element).shadowRoot) {
+				const shadowInputs = (el as Element).shadowRoot!.querySelectorAll<HTMLElement>(TEXT_SELECTOR);
+				for (const input of shadowInputs) {
+					const rect = input.getBoundingClientRect();
+					if (clientX >= rect.left && clientX <= rect.right && clientY >= rect.top && clientY <= rect.bottom) {
+						return input;
+					}
+				}
+			}
+		}
+		return null;
+	}
+
 	exitEditMode() {
 		if (!this.#editing) return;
 		this.#editing = false;
@@ -462,7 +492,15 @@ export class FolkShape extends FolkElement {
 			if (event.type === "touchstart" && event.touches.length === 1) {
 				if (!isValidDragTarget) return;
 
+				// Check if touch is over a text input — enter edit mode instead of dragging
 				const touch = event.touches[0];
+				const textInput = this.#findTextInputAtPoint(touch.clientX, touch.clientY);
+				if (textInput) {
+					this.enterEditMode();
+					requestAnimationFrame(() => textInput.focus());
+					return;
+				}
+
 				this.#lastTouchPos = { x: touch.clientX, y: touch.clientY };
 				this.#isTouchDragging = true;
 				this.#internals.states.add("move");
@@ -520,6 +558,18 @@ export class FolkShape extends FolkElement {
 				// Allow drag from: the host itself, a handle, or a drag handle element
 				if (target !== this && !handle && !isDragHandle) return;
 
+				// If clicking on the shape body (not a handle), check if a text input
+				// is under the pointer — if so, enter edit mode immediately instead of dragging.
+				if (!handle && (target === this || isDragHandle)) {
+					const textInput = this.#findTextInputAtPoint(event.clientX, event.clientY);
+					if (textInput) {
+						this.enterEditMode();
+						// Re-dispatch click so the input receives focus after pointer-events are enabled
+						requestAnimationFrame(() => textInput.focus());
+						return;
+					}
+				}
+
 				if (handle?.startsWith("rotation")) {
 					const parentRotateOrigin = this.#rect.toParentSpace({
 						x: this.#rect.width * this.#rect.rotateOrigin.x,