Correct local file path resolution for ZXDB/WoS mirrors

- Remove optional path prefix and prepend the required local string.
- Avoid hardcoded 'SC' or 'WoS' subdirectories in path mapping.
- Maintain binary state: show local link only if env var is set and file exists.

Signed-off: junie@McFiver.local

src/env.ts

@@ -14,6 +14,10 @@ const serverSchema = z.object({
   ZXDB_FILE_PREFIX: z.string().optional(),
   WOS_FILE_PREFIX: z.string().optional(),
 
+  // Local file paths for mirroring
+  ZXDB_LOCAL_FILEPATH: z.string().optional(),
+  WOS_LOCAL_FILEPATH: z.string().optional(),
+
   // OIDC Configuration
   OIDC_PROVIDER_URL: z.string().url().optional(),
   OIDC_CLIENT_ID: z.string().optional(),