fix: truncate session ID to 36 chars to match server validation

Author: thewh1teagle

src/client/mod.rs

@@ -17,7 +17,9 @@ pub(crate) fn build_session_id(machine_id: &str, app_key: &str, date: &str) -> S
     hasher.update(app_key.as_bytes());
     hasher.update(date.as_bytes());
 
-    format!("{:x}", hasher.finalize())
+    let hash = format!("{:x}", hasher.finalize());
+    // Aptabase server validates SessionId <= 36 chars, SHA-256 hex is 64
+    hash[..36].to_string()
 }
 
 /// Creates a deterministic session ID from machine ID, app key, and current UTC date.

src/client/tests.rs

@@ -29,9 +29,9 @@ fn build_session_id_changes_with_different_machine() {
 }
 
 #[test]
-fn build_session_id_returns_valid_sha256_hex() {
+fn build_session_id_returns_truncated_hex() {
     let id = build_session_id("machine-123", "A-US-abc", "2026-02-13");
-    assert_eq!(id.len(), 64);
+    assert_eq!(id.len(), 36);
     assert!(id.chars().all(|c| c.is_ascii_hexdigit()));
 }