refactor: rename aris to aelis

Rename all references across the codebase: package names,
imports, source IDs, directory names, docs, and configs.

Co-authored-by: Ona <no-reply@ona.com>

packages/aelis-core/src/feed-source.ts

@@ -0,0 +1,86 @@
+import type { ActionDefinition } from "./action"
+import type { Context, ContextEntry } from "./context"
+import type { FeedItem } from "./feed"
+
+/**
+ * Unified interface for sources that provide context, feed items, and actions.
+ *
+ * Sources form a dependency graph — a source declares which other sources
+ * it depends on, and the graph ensures dependencies are resolved before
+ * dependents run.
+ *
+ * Source IDs use reverse domain notation. Built-in sources use `aelis.<name>`,
+ * third parties use their own domain (e.g., `com.spotify`).
+ *
+ * Every method maps to a protocol operation for remote source support:
+ * - `id`, `dependencies`       → source/describe
+ * - `listActions()`            → source/listActions
+ * - `executeAction()`          → source/executeAction
+ * - `fetchContext()`           → source/fetchContext
+ * - `fetchItems()`             → source/fetchItems
+ * - `onContextUpdate()`        → source/contextUpdated (notification)
+ * - `onItemsUpdate()`          → source/itemsUpdated (notification)
+ *
+ * @example
+ * ```ts
+ * const locationSource: FeedSource = {
+ *   id: "aelis.location",
+ *   async listActions() { return { "update-location": { id: "update-location" } } },
+ *   async executeAction(actionId) { throw new UnknownActionError(actionId) },
+ *   async fetchContext() { ... },
+ * }
+ * ```
+ */
+export interface FeedSource<TItem extends FeedItem = FeedItem> {
+	/** Unique identifier for this source in reverse-domain format */
+	readonly id: string
+
+	/** IDs of sources this source depends on */
+	readonly dependencies?: readonly string[]
+
+	/**
+	 * List actions this source supports. Empty record if none.
+	 * Maps to: source/listActions
+	 */
+	listActions(): Promise<Record<string, ActionDefinition>>
+
+	/**
+	 * Execute an action by ID. Throws on unknown action or invalid input.
+	 * Maps to: source/executeAction
+	 */
+	executeAction(actionId: string, params: unknown): Promise<unknown>
+
+	/**
+	 * Subscribe to reactive context updates.
+	 * Called when the source can push context changes proactively.
+	 * Returns cleanup function.
+	 * Maps to: source/contextUpdated (notification, source → host)
+	 */
+	onContextUpdate?(
+		callback: (entries: readonly ContextEntry[]) => void,
+		getContext: () => Context,
+	): () => void
+
+	/**
+	 * Fetch context on-demand.
+	 * Called during manual refresh or initial load.
+	 * Return null if this source cannot provide context.
+	 * Maps to: source/fetchContext
+	 */
+	fetchContext(context: Context): Promise<readonly ContextEntry[] | null>
+
+	/**
+	 * Subscribe to reactive feed item updates.
+	 * Called when the source can push item changes proactively.
+	 * Returns cleanup function.
+	 * Maps to: source/itemsUpdated (notification, source → host)
+	 */
+	onItemsUpdate?(callback: (items: TItem[]) => void, getContext: () => Context): () => void
+
+	/**
+	 * Fetch feed items on-demand.
+	 * Called during manual refresh or when dependencies update.
+	 * Maps to: source/fetchItems
+	 */
+	fetchItems?(context: Context): Promise<TItem[]>
+}