feat: implement PI-090 product tools

electron/coding-runtime/pi/extensions/changed-file.ts

@@ -0,0 +1,35 @@
+import type { ConversationChangeTracker } from '../../../coding-projects/conversation-change-tracker';
+import type { ChangedFileDetailsV1 } from '../../contracts';
+
+export interface ChangedFileToolContext {
+  conversationId: string;
+  runId: string;
+}
+
+export async function reportChangedFiles(
+  tracker: ConversationChangeTracker,
+  context: ChangedFileToolContext,
+  input: unknown,
+) {
+  if (!input || typeof input !== 'object' || Array.isArray(input)) {
+    throw new Error('Changed file report is invalid');
+  }
+  const record = input as Record<string, unknown>;
+  const rawPaths = record.paths ?? (record.path === undefined ? undefined : [record.path]);
+  if (!Array.isArray(rawPaths) || rawPaths.length === 0 || rawPaths.length > 200
+    || rawPaths.some((item) => typeof item !== 'string')) {
+    throw new Error('Changed file report requires relative paths');
+  }
+  const snapshot = await tracker.recordTouchedPaths(
+    context.conversationId,
+    context.runId,
+    rawPaths as string[],
+    record.refresh !== false,
+  );
+  const paths = snapshot.files.map((file) => file.path);
+  const details: ChangedFileDetailsV1 = { schema: 'changed-file.v1', paths };
+  return {
+    content: [{ type: 'text' as const, text: JSON.stringify({ paths, changes: snapshot.files }) }],
+    details,
+  };
+}