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/file_ops.ts

@@ -1,5 +1,5 @@
 import { readFile, readdir, stat } from 'node:fs/promises';
-import { resolve, basename, relative } from 'node:path';
+import { resolve, relative } from 'node:path';
 import { spawn } from 'node:child_process';
 import type { Stats } from 'node:fs';
 import { pathGuard, PathScopeError } from './path_guard.js';
@@ -8,7 +8,7 @@ const MAX_FILE_BYTES = 5 * 1024 * 1024;
 const DEFAULT_VIEW_LINES = 200;
 const MAX_GREP_RESULTS = 200;
 const DEFAULT_GREP_RESULTS = 100;
-const MAX_FIND_RESULTS = 1000;
+const MAX_FIND_RESULTS = 200;
 const DEFAULT_FIND_RESULTS = 100;
 const MAX_DIR_ENTRIES = 500;
 
@@ -44,6 +44,7 @@ export interface GrepResult {
 
 export interface FindFilesResult {
   files: string[];
+  total: number;
   truncated: boolean;
 }
 
@@ -195,15 +196,18 @@ export async function grep(
 export async function findFiles(
   projectRoot: string,
   pattern?: string,
-  opts?: { type?: 'file' | 'dir'; max_results?: number }
+  opts?: { type?: 'file' | 'dir'; max_results?: number; path?: string }
 ): Promise<FindFilesResult> {
   const limit = Math.min(
     Math.max(opts?.max_results ?? DEFAULT_FIND_RESULTS, 1),
     MAX_FIND_RESULTS
   );
+  const target = opts?.path != null
+    ? await pathGuard(projectRoot, opts.path)
+    : projectRoot;
   const args = ['--files'];
   if (pattern) args.push('--glob', pattern);
-  args.push(projectRoot);
+  args.push(target);
 
   return new Promise((resolveP, rejectP) => {
     const child = spawn('rg', args, { cwd: projectRoot });
@@ -243,6 +247,7 @@ export async function findFiles(
       }
       resolveP({
         files,
+        total,
         truncated: total > files.length,
       });
     });