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/memory.rs

@@ -57,7 +57,7 @@ impl Memory {
     /// to nothing, so a path is always produced.
     pub fn path(memory_dir: &Path, name: &str) -> PathBuf {
         let slug = Self::slugify(name).unwrap_or_else(|| "memory".to_string());
-        slug_path(memory_dir, &format!("{}.md", slug))
+        slug_path(memory_dir, &format!("{slug}.md"))
     }
 
     /// Serialize this memory to markdown-with-frontmatter and write it
@@ -72,14 +72,15 @@ impl Memory {
     ///
     /// Return: `Ok(())` on success, or an `io::Error` from directory
     /// creation, the temp write, or the rename.
+    #[allow(clippy::suspicious_open_options)]
     pub fn write(&self, memory_dir: &Path) -> std::io::Result<()> {
         let path = Self::path(memory_dir, &self.name);
         let parent = path.parent().unwrap();
         std::fs::create_dir_all(parent)?;
-        let outcome_line = self.outcome.as_ref().map(|o| format!("outcome: {}", o)).unwrap_or_default();
-        let scope_line = self.scope.as_ref().map(|s| format!("scope: {}", s)).unwrap_or_default();
-        let before_line = self.before_snippet.as_ref().map(|s| format!("before: {}", s)).unwrap_or_default();
-        let after_line = self.after_snippet.as_ref().map(|s| format!("after: {}", s)).unwrap_or_default();
+        let outcome_line = self.outcome.as_ref().map(|o| format!("outcome: {o}")).unwrap_or_default();
+        let scope_line = self.scope.as_ref().map(|s| format!("scope: {s}")).unwrap_or_default();
+        let before_line = self.before_snippet.as_ref().map(|s| format!("before: {s}")).unwrap_or_default();
+        let after_line = self.after_snippet.as_ref().map(|s| format!("after: {s}")).unwrap_or_default();
         let prov_line = if self.provenances.is_empty() {
             String::new()
         } else {
@@ -95,11 +96,11 @@ impl Memory {
         // Write to temp file with fsync for crash safety (prevents
         // partial writes surviving a power loss).
         {
+            use std::io::Write;
             let mut f = std::fs::OpenOptions::new()
                 .create(true)
                 .write(true)
                 .open(&tmp)?;
-            use std::io::Write;
             f.write_all(content.as_bytes())?;
             f.sync_all()?;
         }
@@ -161,7 +162,7 @@ impl Memory {
             before_snippet: front.get("before").cloned().filter(|s| !s.is_empty()),
             after_snippet: front.get("after").cloned().filter(|s| !s.is_empty()),
             provenances: front.get("provenances").cloned()
-                .map(|s| s.split(", ").map(|p| p.to_string()).collect())
+                .map(|s| s.split(", ").map(std::string::ToString::to_string).collect())
                 .unwrap_or_default(),
         })
     }
@@ -185,13 +186,10 @@ impl Memory {
     /// Return: slugs (without extension); empty `Vec` if the directory
     /// can't be read.
     pub fn list(memory_dir: &Path) -> Vec<String> {
-        let entries = match std::fs::read_dir(memory_dir) {
-            Ok(e) => e,
-            Err(_) => return Vec::new(),
-        };
+        let Ok(entries) = std::fs::read_dir(memory_dir) else { return Vec::new() };
         entries
-            .filter_map(|e| e.ok())
-            .filter(|e| e.path().extension().map(|x| x == "md").unwrap_or(false))
+            .filter_map(std::result::Result::ok)
+            .filter(|e| e.path().extension().is_some_and(|x| x == "md"))
             .filter_map(|e| {
                 let name = e.file_name().to_string_lossy().to_string();
                 if name == "MEMORY.md" { return None; }