fix(completion): scoped table lookup, preserve casing, lower Oracle table-function boost

* fix: improve schema-qualified SQL completion

* fix(completion): preserve casing in completion table cache key and relaxed filter

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Co-authored-by: zipg <4047349+zipg@users.noreply.github.com>
Co-authored-by: t8y2 <1156263951@qq.com>

apps/desktop/src/lib/sql/sqlCompletion.ts

@@ -2729,7 +2729,7 @@ function buildOracleTableFunctionItems(prefix: string): SqlCompletionItem[] {
     .map((item) => ({
       ...item,
       type: "function" as const,
-      boost: computeBoost(item.label, prefix) + 2200,
+      boost: computeBoost(item.label, prefix) + 600,
     }));
 }