Keep unreadable revisions for explicit repair

src/modules/coreFeatures/ModuleConflictResolver.ts

@@ -86,8 +86,11 @@ export class ModuleConflictResolver extends AbstractModule {
             return MISSING_OR_ERROR;
         }
         if (rightLeaf == false) {
-            // Conflicted item could not load, delete this.
-            return await this.services.conflict.resolveByDeletingRevision(path, rightRev, "MISSING OLD REV");
+            // A locally unreadable conflict leaf may still be recoverable from another
+            // replica or backup. Keep it visible for explicit repair instead of treating
+            // missing chunks as evidence that the branch is obsolete.
+            this._log(`could not read conflicted revision ${rightRev}:${path}`, LOG_LEVEL_NOTICE);
+            return MISSING_OR_ERROR;
         }
 
         const isSame = leftLeaf.data == rightLeaf.data && leftLeaf.deleted == rightLeaf.deleted;

src/modules/coreFeatures/ModuleConflictResolver.unit.spec.ts

@@ -4,6 +4,7 @@ import {
     DEFAULT_SETTINGS,
     LOG_LEVEL_INFO,
     LOG_LEVEL_NOTICE,
+    MISSING_OR_ERROR,
     type FilePathWithPrefix,
     type MetaEntry,
 } from "@vrtmrz/livesync-commonlib/compat/common/types";
@@ -189,6 +190,28 @@ describe("ModuleConflictResolver independent same-path creation", () => {
 });
 
 describe("ModuleConflictResolver sensible merge hand-off", () => {
+    it("keeps an unreadable non-winner revision unresolved", async () => {
+        const path = "missing-conflict-body.md" as FilePathWithPrefix;
+        const { module, resolveByDeletingRevision, tryAutoMerge } = createModule();
+        tryAutoMerge.mockResolvedValue({
+            leftRev: "3-current",
+            rightRev: "2-unreadable",
+            leftLeaf: {
+                rev: "3-current",
+                data: "Readable current body\n",
+                ctime: 1,
+                mtime: 3,
+                deleted: false,
+            },
+            rightLeaf: false,
+        });
+
+        const result = await module.checkConflictAndPerformAutoMerge(path);
+
+        expect(result).toBe(MISSING_OR_ERROR);
+        expect(resolveByDeletingRevision).not.toHaveBeenCalled();
+    });
+
     it("stores the merged body and removes the resolved conflict leaf", async () => {
         const path = "sensible.md" as FilePathWithPrefix;
         const { module, resolveByDeletingRevision, tryAutoMerge } = createModule();