Migrate from window.electron to tauri IPC functions across components

- Replaced `window.electron.invoke` calls with equivalent `tauri` function calls for all IPC interactions.
- Removed `electron.d.ts` TypeScript definitions as they are no longer needed.
- Updated related logic for offline/online state synchronization.
- Added `types.rs` and `shared/mod.rs` modules to support Tauri IPC integration with Rust enums and shared logic.
- Refactored IPC request queues to use updated handler names for consistency with Tauri.

src-tauri/src/helpers.rs

@@ -0,0 +1,59 @@
+use chrono::Utc;
+use regex::Regex;
+
+
+/// Returns the current UNIX timestamp in seconds.
+/// Equivalent to TS `System.timeStampInSeconds()`.
+pub fn timestamp_in_seconds() -> i64 {
+    std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .map(|duration| duration.as_secs() as i64)
+        .unwrap_or(0)
+}
+
+/// Creates a new UUID v4 string, or reuses an existing ID if provided.
+/// Equivalent to TS `System.createUniqueId()`.
+pub fn create_unique_id(existing_id: Option<&str>) -> String {
+    match existing_id {
+        Some(id) => id.to_string(),
+        None => uuid::Uuid::new_v4().to_string(),
+    }
+}
+
+/// Returns the current date as an ISO 8601 string.
+/// Equivalent to TS `System.getCurrentDate()`.
+pub fn get_current_date() -> String {
+    Utc::now().to_rfc3339()
+}
+
+/// Converts an ISO date string to a MySQL-compatible date (YYYY-MM-DD).
+/// Equivalent to TS `System.dateToMySqlDate()`.
+pub fn date_to_mysql_date(iso_date_string: &str) -> String {
+    match chrono::DateTime::parse_from_rfc3339(iso_date_string) {
+        Ok(date_object) => date_object.format("%Y-%m-%d").to_string(),
+        Err(_) => iso_date_string.to_string(),
+    }
+}
+
+/// Converts HTML content to plain text by stripping tags and decoding entities.
+/// Equivalent to TS `System.htmlToText()`.
+pub fn html_to_text(html_node: &str) -> String {
+    let mut text: String = html_node.to_string();
+    let p_regex: Regex = Regex::new(r"(?i)</?p[^>]*>").unwrap();
+    let br_regex: Regex = Regex::new(r"(?i)<br\s*/?>").unwrap();
+    let span_heading_regex: Regex = Regex::new(r"(?i)</?(span|h[1-6])[^>]*>").unwrap();
+    text = p_regex.replace_all(&text, "\n").to_string();
+    text = br_regex.replace_all(&text, "\n").to_string();
+    text = span_heading_regex.replace_all(&text, "").to_string();
+    text = text.replace("&apos;", "'");
+    text = text.replace("&quot;", "\"");
+    text = text.replace("&amp;", "&");
+    text = text.replace("&lt;", "<");
+    text = text.replace("&gt;", ">");
+    text = text.replace("&#39;", "'");
+    let double_newline_regex: Regex = Regex::new(r"\r?\n\s*\n").unwrap();
+    text = double_newline_regex.replace_all(&text, "\n").to_string();
+    let spaces_regex: Regex = Regex::new(r"[ \t]+").unwrap();
+    text = spaces_regex.replace_all(&text, " ").to_string();
+    text.trim().to_string()
+}