fix(coding-agent): corrected gutter marker alignment in diff rendering

- Added `CodeFrameMarker` and `formatCodeFrameLine()` to centralize code-frame gutter formatting.
- Extended diff rendering to preserve `|` and `│` separators, aligning gutter markers and line numbers.
- Reworked AST, grep, hashline, Vim, and diff renderers to use shared line formatting with computed `lineNumberWidth`.
- Updated atom editing flow and tests, including `resolveAtomEntryPaths` migration and new loc-based/edge-case coverage.
- Adjusted benchmark runner early-stop configuration by passing `buildEarlyStop` through prompt collection.

packages/coding-agent/src/edit/diff.ts

@@ -50,7 +50,6 @@ export class ApplyPatchError extends Error {
 // Diff String Generation
 // ═══════════════════════════════════════════════════════════════════════════
 
-
 function formatNumberedDiffLine(prefix: "+" | "-" | " ", lineNum: number, content: string): string {
 	return `${prefix}${lineNum}|${content}`;
 }
@@ -63,7 +62,6 @@ export function generateDiffString(oldContent: string, newContent: string, conte
 	const parts = Diff.diffLines(oldContent, newContent);
 	const output: string[] = [];
 
-
 	let oldLineNum = 1;
 	let newLineNum = 1;
 	let lastWasChange = false;