fix(cli): scan modern module extensions

## Summary
Include modern JavaScript and TypeScript module extensions in the
repo-wide CLI source scan so `codecontext --report` sees tagged files.

## Changes
- add `.mjs`, `.cjs`, `.mts`, and `.cts` to the CLI source matcher
- add a CLI regression test covering modern module extensions in repo scans

## Testing
- pnpm --filter @recallnet/codecontext-cli test

fixes #3

Author: astrochicken-hatch

packages/cli/src/files.ts

@@ -3,7 +3,8 @@ import { join } from "node:path";
 
 const IGNORED_DIRS = new Set([".git", ".turbo", "coverage", "dist", "node_modules"]);
 
-const SOURCE_EXTENSIONS = /\.(ts|tsx|js|jsx|py|rs|go|java|c|cpp|h|hpp|rb|swift|kt)$/;
+const SOURCE_EXTENSIONS =
+  /\.(ts|tsx|mts|cts|js|jsx|mjs|cjs|py|rs|go|java|c|cpp|h|hpp|rb|swift|kt)$/;
 
 export function isSourceFile(relativePath: string): boolean {
   return SOURCE_EXTENSIONS.test(relativePath);

packages/cli/test/files.test.ts

@@ -0,0 +1,45 @@
+import { mkdtempSync, mkdirSync, rmSync, writeFileSync } from "node:fs";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+
+import { afterEach, describe, expect, it } from "vitest";
+
+import { findSourceFiles, isSourceFile } from "../src/files.js";
+
+const tempDirs: string[] = [];
+
+afterEach(() => {
+  for (const dir of tempDirs.splice(0)) {
+    rmSync(dir, { recursive: true, force: true });
+  }
+});
+
+describe("isSourceFile", () => {
+  it("matches modern JS and TS module extensions", () => {
+    expect(isSourceFile("src/entry.mjs")).toBe(true);
+    expect(isSourceFile("src/entry.cjs")).toBe(true);
+    expect(isSourceFile("src/entry.mts")).toBe(true);
+    expect(isSourceFile("src/entry.cts")).toBe(true);
+  });
+});
+
+describe("findSourceFiles", () => {
+  it("includes modern JS and TS module extensions in repo scans", () => {
+    const root = mkdtempSync(join(tmpdir(), "codecontext-cli-files-"));
+    tempDirs.push(root);
+
+    mkdirSync(join(root, "src"), { recursive: true });
+    writeFileSync(join(root, "src", "entry.mjs"), "// @context decision - ESM module\n");
+    writeFileSync(join(root, "src", "entry.cjs"), "// @context decision - CommonJS module\n");
+    writeFileSync(join(root, "src", "entry.mts"), "// @context decision - TS ESM module\n");
+    writeFileSync(join(root, "src", "entry.cts"), "// @context decision - TS CJS module\n");
+    writeFileSync(join(root, "src", "ignored.md"), "@context decision - not a source file\n");
+
+    expect(findSourceFiles(root)).toEqual([
+      join(root, "src", "entry.cjs"),
+      join(root, "src", "entry.cts"),
+      join(root, "src", "entry.mjs"),
+      join(root, "src", "entry.mts"),
+    ]);
+  });
+});