Change LocalData timestamp fields from u32 to DateTime<Utc> to support JavaScript timestamps (#214)

## 🎟️ Tracking

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## 📔 Objective
This PR updates the LocalData and LocalDataView structs to use
DateTime<Utc> instead of u32 for timestamp fields (lastUsedDate and
lastLaunched). The timestamp sent from the TS client can exceed the u32
max value, which throws an error.
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you're fixing or new feature you're adding. -->

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- Written new unit and / or integration tests where applicable
- Protected functional changes with optionality (feature flags)
- Used internationalization (i18n) for all UI strings
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- Updated any necessary documentation (Confluence, contributing docs) or
informed the documentation
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Author: gbubemismith

crates/bitwarden-vault/src/cipher/local_data.rs

@@ -1,5 +1,6 @@
 use bitwarden_core::key_management::{KeyIds, SymmetricKeyId};
 use bitwarden_crypto::{CryptoError, Decryptable, Encryptable, KeyStoreContext};
+use chrono::{DateTime, Utc};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 #[cfg(feature = "wasm")]
@@ -10,17 +11,17 @@ use tsify_next::Tsify;
 #[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
 #[cfg_attr(feature = "wasm", derive(Tsify), tsify(into_wasm_abi, from_wasm_abi))]
 pub struct LocalData {
-    last_used_date: Option<u32>,
-    last_launched: Option<u32>,
+    last_used_date: Option<DateTime<Utc>>,
+    last_launched: Option<DateTime<Utc>>,
 }
 
 #[derive(Serialize, Deserialize, Debug, JsonSchema, Clone)]
 #[serde(rename_all = "camelCase", deny_unknown_fields)]
 #[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
 #[cfg_attr(feature = "wasm", derive(Tsify), tsify(into_wasm_abi, from_wasm_abi))]
 pub struct LocalDataView {
-    last_used_date: Option<u32>,
-    last_launched: Option<u32>,
+    last_used_date: Option<DateTime<Utc>>,
+    last_launched: Option<DateTime<Utc>>,
 }
 
 impl Encryptable<KeyIds, SymmetricKeyId, LocalData> for LocalDataView {