fix: make line_ranges optional in read_file tool schema (#9254)

The OpenAI tool schema required both 'path' and 'line_ranges' in FileEntry,
but the TypeScript type definition marks lineRanges as optional. This caused
the AI to fail when trying to read files without specifying line_ranges.

Changes:
- Updated read_file tool schema to only require 'path' parameter
- line_ranges remains available but optional, matching TypeScript types
- Aligns with implementation which treats lineRanges as optional throughout

Fixes issue where read_file tool kept failing with missing parameters.

src/core/prompts/tools/native-tools/read_file.ts

@@ -30,7 +30,7 @@ export const read_file = {
 								},
 							},
 						},
-						required: ["path", "line_ranges"],
+						required: ["path"],
 						additionalProperties: false,
 					},
 					minItems: 1,