Show workspace commits clearly in Changes (#2350)

* feat(commits): distinguish workspace history from base commits

Keep every workspace commit visible while bounding base history to ten
context commits, and make push and base state readable in the commit rail.

* fix(commits): preserve history when base refs disappear

Fall back to recent HEAD history for stale saved bases, and reject truncated
git output instead of presenting an incomplete commit list.

* fix(commits): classify history against the current base

Use the furthest-ahead local or remote base for classification, and re-infer
base history when saved worktree metadata points to a deleted branch.

packages/app/src/i18n/resources/en.ts

@@ -805,7 +805,7 @@ export const en = {
         deletedFile: "Deleted",
         commits: {
           title: "Commits",
-          countLabel: "{{count}} recent commits",
+          countLabel: "{{count}} workspace commits",
           fileDiffEmpty: "No changes to display",
           fileDiffError: "Failed to load file diff",
           loading: "Loading commits…",