Fix Mail Maildir paths and oCIS auth

Mail: INBOX is a subfolder (INBOX/cur), not the account root.
Removed special-case mapping that pointed INBOX to root dir.

Files: oCIS user may differ from MCP user (e.g. stefan -> admin).
Added _ocis_user() mapping for WebDAV paths and auth.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

files/server.py

@@ -22,8 +22,12 @@ OCIS_CREDS = {u: (d['username'], d['password']) for u, d in _cfg['ocis_users'].i
 mcp = FastMCP("Files", stateless_http=True,
               transport_security={"enable_dns_rebinding_protection": False})
 
+def _ocis_user(u):
+    c = OCIS_CREDS.get(u)
+    return c[0] if c else u
+
 def _auth(u): c = OCIS_CREDS.get(u); return httpx.BasicAuth(c[0], c[1]) if c else None
-def _dav(u, p=""): return f"{OCIS}/remote.php/dav/files/{u}/{p.lstrip('/')}"
+def _dav(u, p=""): return f"{OCIS}/remote.php/dav/files/{_ocis_user(u)}/{p.lstrip('/')}"
 
 def _propfind(user, path="", depth=1):
     body = '<?xml version="1.0"?><d:propfind xmlns:d="DAV:"><d:prop><d:resourcetype/><d:displayname/><d:getcontentlength/><d:getlastmodified/><d:getcontenttype/></d:prop></d:propfind>'
@@ -35,7 +39,7 @@ def _parse_pf(xml, user):
     entries = []
     try: root = ET.fromstring(xml)
     except: return entries
-    bp = f"/remote.php/dav/files/{user}/"
+    bp = f"/remote.php/dav/files/{_ocis_user(user)}/"
     for resp in root.findall("d:response", ns):
         href = resp.findtext("d:href", "", ns) or ""
         rel = href.split(bp, 1)[-1].rstrip("/") if bp in href else href.rstrip("/")