A version that was not two spellings of itself

The Updates page read "v1.0.0 (reports 1.0.0)". That note exists to warn
that a tag was cut before the version bump -- a release nobody can
identify afterwards -- and it was firing on two ways of writing one
version, because `git describe` answers with the tag's name and tags here
carry a `v`.

Stripped in `_describe`, where `resolve_target` has always stripped it and
where the docstring already promised the stripped form. The mismatch check
then compares two things spelled the same way, and still reports a tag
that really does disagree; there is a test for each half.

Found by cutting the first release, which is the only place it could have
been found.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/lembas/services/updates.py

@@ -340,7 +340,7 @@ def resolve_target(root: Path, channel: str, branch: str) -> Target | None:
             return None
         return Target(
             ref=tag,
-            label=tag.lstrip("v"),
+            label=tag.removeprefix("v"),
             sha=commit.sha,
             subject=commit.subject,
             notes=_notes_for(root, tag),
@@ -362,9 +362,16 @@ def _describe(root: Path) -> str:
     bare short sha when nothing has ever been tagged. That last case is why
     `--always` is there: without it this fails outright on a repository with no
     tags, which is every repository before its first release.
+
+    The leading `v` comes off, because git answers with the **tag's name** and
+    tags here are `v1.0.0` while `__version__` is `1.0.0`. Without this the page
+    read "v1.0.0 (reports 1.0.0)" -- a note whose whole purpose is to flag a tag
+    cut before a version bump, firing on two spellings of the same version. The
+    first release is what showed it. `resolve_target` has always stripped it for
+    the same reason, and this docstring already promised the stripped form.
     """
     code, output = _git(["describe", "--tags", "--always", "--dirty="], cwd=root)
-    return output if code == 0 else ""
+    return output.removeprefix("v") if code == 0 else ""
 
 
 def read(*, fetch: bool = False) -> State:
@@ -418,8 +425,8 @@ def read(*, fetch: bool = False) -> State:
     # Exactly at a tag whose name disagrees with the version this process
     # reports. No subprocess: `running` and `__version__` are both already here.
     mismatch = ""
-    if RELEASE_TAG.match(running) and running.lstrip("v") != __version__:
-        mismatch = running.lstrip("v")
+    if RELEASE_TAG.match(running) and running != __version__:
+        mismatch = running
 
     return State(
         **base,