fix(event): correctly parse project/event-id in view command (#1263)

This PR fixes an issue where `sentry event view <project>/<event-id>`
would fail with a `ContextError: Event ID is required.`

The root cause was that `parseSingleArg` in `src/commands/event/view.ts`
was incorrectly delegating single-slash arguments like
`project/event-id` to `parseSlashSeparatedArg`. The
`parseSlashSeparatedArg` function, when encountering a single slash,
assumes the format is `org/project` and that an event ID is missing,
leading it to throw the `ContextError`.

The fix adds a specific check within `parseSingleArg` for the
`project/event-id` pattern (where the part after the slash is a valid
hex event ID) before the delegation to `parseSlashSeparatedArg`. This
ensures that such arguments are correctly parsed and handled, preventing
the erroneous `ContextError`.

Fixes
[CLI-CG](https://sentry.sentry.io/issues/7322504022/?seerDrawer=true)

<sub>Comment `@sentry <feedback>` on this PR to have Autofix iterate on
the changes.</sub>

Co-authored-by: sentry[bot] <39604003+sentry[bot]@users.noreply.github.com>

Author: sentry[bot]

src/commands/event/view.ts

@@ -228,6 +228,17 @@ function parseSingleArg(arg: string): ParsedPositionalArgs {
         issueShortId: beforeSlash,
       };
     }
+
+    // "project/EVENT-ID" → project slug + hex event ID.
+    // e.g., "my-project/abc123def456abc123def456abc123de"
+    // Must be checked before parseSlashSeparatedArg, which throws ContextError
+    // for any single-slash arg, assuming it's "org/project" with a missing ID.
+    if (afterSlash && HEX_ID_RE.test(normalizeHexId(afterSlash))) {
+      return {
+        eventId: normalizeHexId(afterSlash),
+        targetArg: beforeSlash,
+      };
+    }
   }
 
   const { id: eventId, targetArg } = parseSlashSeparatedArg(