fix: skip flaky tests for Windows symlinks and receiver patience

[abakum]

No description provided.

[abakum]

fix: skip flaky tests for Windows symlinks and receiver patience

Fix 1: Skip symlink test on Windows

Problem: TestCrocSymlink fails on Windows because creating symlinks requires elevated privileges (Run as Administrator) or Developer Mode enabled. On CI running Windows, this test fails unless the runner has special configuration.

Solution: Add t.Skip("skipping: symlinks require admin privileges on Windows") at the beginning of the test when runtime.GOOS == "windows".

Fix 2: Skip receiver stdout test with invalid secret

Problem: After the relay room authorization changes (PR #1115), the receiver now waits patiently for the sender — up to one minute on someone else's relay, or three hours on their own. The test TestReceiverStdoutWithInvalidSecret expects the receiver to fail immediately with an invalid secret, which no longer happens.

Solution: Skip the test with a message explaining the behavioral change: "The receiver is now patient: it will wait for the sender for one minute on someone else's relay, or three hours on its own."

Note: This PR should be submitted after PR #1115 is merged, otherwise the skip reason for test 2 won't make sense.