fix(hashline-edit): do not restore indentation for replace_lines

- applyReplaceLines: use stripped array directly instead of restoreLeadingIndent
- applySetLine: keep restoreLeadingIndent (1:1 replacement needs indent preservation)
- Added test case for replace_lines preserving new line indentation
- All 3025 tests pass

🤖 Generated with OhMyOpenCode assistance

src/tools/hashline-edit/edit-operations.test.ts

@@ -127,4 +127,15 @@ describe("hashline edit operations", () => {
     //#then
     expect(result).toEqual(["before", "new 1", "new 2", "after"])
   })
+
+  it("does not restore indentation for replace_lines", () => {
+    //#given
+    const lines = ["if (x) {", "  return 1", "  return 2", "}"]
+
+    //#when
+    const result = applyReplaceLines(lines, anchorFor(lines, 2), anchorFor(lines, 3), ["return 3", "return 4"])
+
+    //#then
+    expect(result).toEqual(["if (x) {", "return 3", "return 4", "}"])
+  })
 })

src/tools/hashline-edit/edit-operations.ts

@@ -124,12 +124,7 @@ export function applyReplaceLines(
 
   const result = [...lines]
   const stripped = stripRangeBoundaryEcho(lines, startLine, endLine, toNewLines(newText))
-  const newLines = stripped.map((entry, idx) => {
-    const oldLine = lines[startLine - 1 + idx]
-    if (!oldLine) return entry
-    return restoreLeadingIndent(oldLine, entry)
-  })
-  result.splice(startLine - 1, endLine - startLine + 1, ...newLines)
+  result.splice(startLine - 1, endLine - startLine + 1, ...stripped)
   return result
 }