fix: let a discard asked before a move lands win over the edits it drops

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015vn1jCHUcAdaG9C4NsUehF

frontend/src/lib/itemStore.svelte.ts

@@ -180,6 +180,8 @@ class Entry<V> {
 	/** Replaced by an entry that moved onto its key: it no longer owns the row there, and a write
 	 *  reaching its turn does nothing, as its handles show the item that replaced it. */
 	retired = false
+	/** Discards asked and still waiting for their turn. */
+	discardsAsked = 0
 	/** The command running now, past its turn: what a move onto this key waits for. */
 	running: Promise<unknown> | undefined
 	/** The entries a save of this entry waits for before moving: a move skips waiting for any
@@ -421,7 +423,9 @@ class Entry<V> {
 	 *  changed from its own deployed side, so they stay a draft over what this entry deployed.
 	 *  Compared exactly, as a save is: a field the draft comparison ignores (run-as) is an edit. */
 	carryEditsOf(old: Entry<V>): void {
-		if (old.value === undefined || this.value === undefined) return
+		// A discard asked before the move landed wins over the edits it was asked to drop; had it
+		// run first, it would have dropped anything typed after it too.
+		if (old.value === undefined || this.value === undefined || old.discardsAsked > 0) return
 		// Not loaded yet (its read waits behind the move): only an outside write can have filled it,
 		// and nothing has persisted that write but this entry.
 		if (!old.loaded) {
@@ -460,7 +464,9 @@ class Entry<V> {
 	}
 
 	discard(): Promise<DiscardOutcome> {
+		this.discardsAsked++
 		return this.run(async () => {
+			this.discardsAsked--
 			if (!this.loaded || this.retired) return { removed: false }
 			if (this.origin === 'draft') {
 				const kept = snapshot(this.value)

frontend/src/lib/itemStore.test.ts

@@ -586,6 +586,36 @@ describe('item store: one entry per key', () => {
 		expect(rows.writes.at(-1)).toEqual({ path: 'u/me/b', value: chat })
 	})
 
+	it('lets a discard asked before a move lands win over the edits it drops', async () => {
+		const rows = fakeRows()
+		const store = createItemStore(rows.port)
+		const gate = deferred()
+		const b = { ...deployedRes, path: 'u/me/b' }
+		const temporary = newItemPath()
+		const { handle: moving } = store.acquire(
+			{ workspace: 'w', kind: 'resource', path: temporary },
+			{ workspace: 'w', path: temporary, template: b },
+			adapter({}, () => gate.promise)
+		)
+		await settle()
+		moving.value = { ...b, args: { a: 2 } }
+		const moved = moving.save()
+		await settle()
+		const { handle: opened } = store.acquire(
+			{ workspace: 'w', kind: 'resource', path: 'u/me/b' },
+			{ workspace: 'w', path: 'u/me/b' },
+			adapter({ deployed: b })
+		)
+		store.bridge.seed('w', 'resource', 'u/me/b', { ...b, description: 'written by the chat' })
+		store.bridge.discard('w', 'resource', 'u/me/b')
+
+		gate.resolve()
+		expect(await moved).toMatchObject({ ok: true, moved: true })
+		expect(opened.value).toEqual({ ...b, args: { a: 2 } })
+		expect(opened.dirty).toBe(false)
+		expect(rows.writes.at(-1)).toEqual({ path: 'u/me/b', value: null })
+	})
+
 	it('keeps a change the draft comparison ignores in an editor a move replaces', async () => {
 		type Sched = { path: string; summary: string; permissioned_as?: string }
 		const rows = fakeRows()