ci: add GitHub Actions workflows with semantic-release auto-versioning

chore: fix all 702 clippy warnings across codebase
- auto-fix 475 via cargo clippy --fix
- fix remaining 227 manually: uninlined_format_args, redundant_closure, match_same_arms,
  underscore_binding, format_push_string, items_after_statements, needless_pass_by_value,
  clone_on_copy, case_sensitive_extension, single_match/let-else, write_with_newline,
  and other clippy lints

src/model/editlog.rs

@@ -43,18 +43,12 @@ impl EditLog {
     /// `MAX_MEMORY_ENTRIES` entries. The full history is preserved on disk
     /// regardless of the in-memory limit.
     fn load_from_disk(path: &std::path::Path) -> Vec<EditLogEntry> {
-        let file = match std::fs::File::open(path) {
-            Ok(f) => f,
-            Err(_) => return Vec::new(),
-        };
         use std::io::{BufRead, BufReader};
+        let Ok(file) = std::fs::File::open(path) else { return Vec::new() };
         let reader = BufReader::new(file);
         let mut entries: Vec<EditLogEntry> = Vec::new();
         for line in reader.lines() {
-            let line = match line {
-                Ok(l) => l,
-                Err(_) => continue,
-            };
+            let Ok(line) = line else { continue };
             if let Ok(entry) = serde_json::from_str::<EditLogEntry>(&line) {
                 // Keep only the most recent entries in memory
                 if entries.len() >= MAX_MEMORY_ENTRIES {
@@ -81,6 +75,7 @@ impl EditLog {
     /// Return: `Ok(())` on success; an `io::Error` if serialization or
     /// any filesystem operation fails.
     pub fn append(&mut self, entry: EditLogEntry) -> std::io::Result<()> {
+        use std::io::Write;
         let line = serde_json::to_string(&entry)? + "\n";
         // Ensure parent directory exists; fall back to the current
         // directory if path has no parent (should not happen in practice
@@ -92,7 +87,6 @@ impl EditLog {
             .create(true)
             .append(true)
             .open(&self.path)?;
-        use std::io::Write;
         file.write_all(line.as_bytes())?;
         file.sync_all()?;
         self.entries.push(entry);