perf: remove totally redundant and highly allocating .to_lowercase() calls from search endpoints

server/src/handlers_v2/meta.rs

@@ -68,7 +68,7 @@ impl McpTool for QueryDecisionsHandler {
         let data = state.adrs.read_with(|adrs| {
             let filtered: Vec<_> = adrs.iter().filter(|a| {
                 if let Some(q) = &req.query {
-                    let q = q.to_lowercase();
+                    let q = q;
                     contains_ignore_ascii_case(&a.title, &q)
                         || contains_ignore_ascii_case(&a.context, &q)
                         || contains_ignore_ascii_case(&a.decision, &q)
@@ -129,7 +129,7 @@ impl McpTool for SearchErrorFixesHandler {
 
     async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
         let req: SearchErrorFixesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
-        let q = req.query.to_lowercase();
+        let q = req.query;
         let data = state.error_fixes.read_with(|fixes| {
             let filtered: Vec<_> = fixes.iter().filter(|f| {
                 contains_ignore_ascii_case(&f.signature, &q)
@@ -399,7 +399,7 @@ impl McpTool for OmniSearchHandler {
             }
         });
 
-        let q = req.query.to_lowercase();
+        let q = req.query;
         let tech_debts = state.tech_debts.read_with(|debts| {
             debts.iter().filter(|d| {
                 req.namespace.as_ref().is_none_or(|ns| d.namespace == *ns)