batch3 T4 review fixes: harmonize find_files cap; delegate to file_ops

- file_ops.MAX_FIND_RESULTS: 1000 -> 200 to match existing tool cap and
  preserve LLM behavior
- tools.find_files now delegates to file_ops.findFiles (parallels how
  grep already delegates); drops ~50 LOC of duplicated path resolution
  and rg subprocess
- Drop unused basename import in file_ops

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/server/src/services/tools.ts

@@ -1,9 +1,8 @@
 import { readFile, readdir, stat } from 'node:fs/promises';
 import { resolve, basename, relative } from 'node:path';
-import { spawn } from 'node:child_process';
 import { z } from 'zod';
 import { pathGuard, PathScopeError } from './path_guard.js';
-import { grep as fileOpsGrep } from './file_ops.js';
+import { grep as fileOpsGrep, findFiles as fileOpsFindFiles } from './file_ops.js';
 
 const MAX_FILE_BYTES = 5 * 1024 * 1024;
 const DEFAULT_VIEW_LINES = 200;
@@ -249,55 +248,21 @@ export const findFiles: ToolDef<FindFilesInputT> = {
     },
   },
   async execute(input, projectRoot) {
-    const target = await pathGuard(projectRoot, input.path ?? projectRoot);
     const limit = Math.min(
       Math.max(input.max_results ?? DEFAULT_FIND_RESULTS, 1),
       MAX_FIND_RESULTS
     );
-    return await new Promise((resolveP, rejectP) => {
-      const args = ['--files', '--glob', input.pattern, target];
-      const child = spawn('rg', args, { cwd: projectRoot });
-      const paths: string[] = [];
-      let total = 0;
-      let buf = '';
-      let stderr = '';
-      child.stdout.setEncoding('utf8');
-      child.stderr.setEncoding('utf8');
-      child.stdout.on('data', (chunk: string) => {
-        buf += chunk;
-        let idx;
-        while ((idx = buf.indexOf('\n')) >= 0) {
-          const line = buf.slice(0, idx);
-          buf = buf.slice(idx + 1);
-          if (!line) continue;
-          total++;
-          if (paths.length < limit) {
-            paths.push(relative(projectRoot, line) || line);
-          }
-        }
-      });
-      child.stderr.on('data', (chunk: string) => {
-        stderr += chunk;
-      });
-      child.on('error', (err) => rejectP(err));
-      child.on('close', (code) => {
-        if (code === 2) {
-          rejectP(new Error(`ripgrep failed: ${stderr.slice(0, 300)}`));
-          return;
-        }
-        if (buf.length > 0) {
-          total++;
-          if (paths.length < limit) {
-            paths.push(relative(projectRoot, buf) || buf);
-          }
-        }
-        resolveP({
-          paths,
-          total,
-          truncated: total > paths.length,
-        });
-      });
+    // Delegate to file_ops.findFiles; reshape { files, total, truncated } to
+    // preserve the LLM-visible output format { paths, total, truncated }
+    const result = await fileOpsFindFiles(projectRoot, input.pattern, {
+      path: input.path,
+      max_results: limit,
     });
+    return {
+      paths: result.files,
+      total: result.total,
+      truncated: result.truncated,
+    };
   },
 };