fix: prune dist/data before rsync in _trigger_rebuild and manual rebuild endpoint

Same fix as cea1dbc (post-receive hook) but missed in server.py: Astro resolves
the public/data symlink and copies all activity JSON into dist/; without pruning,
every Strava sync / upload / edit that triggers a full build + rsync duplicates
GBs of data into the nginx webroot.

Both rsync callsites now rm -rf dist/data + pass --exclude=data/ to rsync.

bincio/serve/server.py

@@ -375,8 +375,15 @@ def _trigger_rebuild(handle: str) -> None:
                                   _handle, result.returncode, result.stdout, result.stderr)
                     else:
                         log.info("rebuild[%s]: build done, rsyncing", _handle)
+                        # Prune dist/data/ before rsync: Astro resolves the
+                        # public/data symlink and copies all activity JSON into
+                        # dist/, but nginx already serves /data/ directly from
+                        # the live data dir — rsyncing it would duplicate GBs.
+                        dist_data = Path(_site_dir) / "dist" / "data"
+                        if dist_data.exists():
+                            shutil.rmtree(dist_data)
                         rsync = subprocess.run(
-                            ["rsync", "-a", "--delete",
+                            ["rsync", "-a", "--delete", "--exclude=data/",
                              f"{_site_dir}/dist/", _webroot + "/"],
                             capture_output=True,
                             text=True,
@@ -707,8 +714,12 @@ async def admin_rebuild_sync(
     }
 
     if result.returncode == 0 and webroot:
+        dist_data = site_dir / "dist" / "data"
+        if dist_data.exists():
+            shutil.rmtree(dist_data)
         rsync = subprocess.run(
-            ["rsync", "-a", "--delete", f"{site_dir}/dist/", str(webroot) + "/"],
+            ["rsync", "-a", "--delete", "--exclude=data/",
+             f"{site_dir}/dist/", str(webroot) + "/"],
             capture_output=True, text=True, timeout=120,
         )
         resp["rsync_returncode"] = rsync.returncode