Delete the dead Session model

Nothing has referenced it since the auth cutover: the session is an httpOnly
cookie this app can neither read nor construct, so there is no session type
for it to hold.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

CLAUDE.md

@@ -68,5 +68,5 @@ login carrying this URL as the return target; 403 (or a signed-in account withou
 `calendar` permission) shows a refusal with Reload/Sign out; anything else shows "cannot be
 reached". None of those three redirect, on purpose.
 
-**Dead since the cutover, kept only because deleting files needs a decision:**
+**Dead since the cutover:** the unrouted `LoginComponent`. `src/app/models/session.ts` is
-`src/app/models/session.ts` and the unrouted `LoginComponent`.
+gone; there is no session type here any more, because this app never handles one.

src/app/models/session.ts

@@ -1,4 +0,0 @@
-export interface Session {
-	sessionId: number;
-	sessionKey: string;
-}