fix(paths): accept literal tilde-digit filenames

Catalog generation and peer install/download validation rejected any path component containing a tilde followed by digits, even when the component was a valid long filename such as Bosons TD Gold~1.w3m. Remove the heuristic from all three validators and retain the existing device-name and portable-alias checks. Add a regression test for the literal filename so catalog publication and later path validation agree.

Test Plan:
- just clippy (passed)
- just test (passed)
- git diff --check (passed)

crates/lanspread-peer/src/download/manifest.rs

@@ -370,9 +370,6 @@ fn validate_component(component: &str) -> eyre::Result<()> {
     if is_windows_device_name(device_stem) {
         eyre::bail!("download path uses a Windows device name: {component}");
     }
-    if looks_like_dos_short_name(component) {
-        eyre::bail!("download path resembles a Windows short-name alias: {component}");
-    }
     Ok(())
 }
 
@@ -393,16 +390,6 @@ fn is_windows_device_name(stem: &str) -> bool {
             })
 }
 
-fn looks_like_dos_short_name(component: &str) -> bool {
-    let stem = component.split('.').next().unwrap_or_default();
-    stem.rsplit_once('~').is_some_and(|(prefix, suffix)| {
-        !prefix.is_empty()
-            && !suffix.is_empty()
-            && suffix.len() <= 6
-            && suffix.bytes().all(|byte| byte.is_ascii_digit())
-    })
-}
-
 fn validate_existing_destination(
     game_root: &Path,
     components: &[&str],