refactor: replace all explicit any types with proper TypeScript types

Backend resolvers: typed enrichArticle/enrichVideo/enrichModel with DB
and $inferSelect types, SQL<unknown>[] for conditions arrays, proper
enum casts for status/role fields, $inferInsert for .set() updates,
typed raw SQL result rows in gamification, ReplyLike interface for
ctx.reply in auth. Frontend: typed catch blocks with Error/interface
casts, isActiveLink param, adminGetUser response, tags filter callback.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/frontend/src/routes/signup/+page.svelte

@@ -47,8 +47,9 @@
       await register(email, password, firstName, lastName);
       toast.success($_("auth.signup.toast_register", { values: { email } }));
       goto("/login");
-    } catch (err: any) {
-      const raw = err.response?.errors?.[0]?.message ?? err.message;
+    } catch (err) {
+      const e = err as { response?: { errors?: Array<{ message: string }> }; message?: string };
+      const raw = e.response?.errors?.[0]?.message ?? e.message;
       error = raw === "Email already registered" ? $_("auth.signup.error_email_taken") : raw;
       isError = true;
     } finally {