refactor: fix all P0/P1/P2 bugs and architecture issues

Bug fixes (from bugs/ directory):

- Fix cross-module DB queries in 9 modules (homework, grades, parent, diagnostic, elective, proctoring, notifications, scheduling, classes) by routing through data-access functions

- Fix shared/lib <-> auth circular dependency via new session.ts module

- Fix divide-by-zero guard in grades data-access

- Fix audit export data truncation (paginated fetch for full datasets)

- Fix missing transactions in homework grading and elective lottery

- Fix missing revalidatePath in course-plans actions

- Fix frontend permission checks using requirePermission instead of requireAuth

- Fix dashboard role routing using session.user.roles

- Fix student auth pattern (migrate getDemoStudentUser to users module)

- Fix ActionState return type handling in components

Code quality fixes:

- Remove 60+ as type assertions (replace with type guards)

- Remove non-null assertions (use optional chaining or explicit checks)

- Convert dynamic imports to static imports (grades, diagnostic)

- Add React.cache() wrapping for read functions

- Parallelize independent queries with Promise.all

- Add explicit return types to 30+ arrow functions

- Replace any with unknown + type guards

- Fix import type for type-only imports

- Add Zod validation schemas for classes and diagnostic modules

- Extract duplicate code (normalizeRoleName, normalizeBcryptHash, logger IP extraction)

- Add console.error to silent catch blocks

- Fix permission naming consistency (exam:proctor_read -> exam:proctor:read)

Architecture doc sync:

- Update 004_architecture_impact_map.md and 005_architecture_data.json

- Update management-modules-audit.md for P0-7 cross-module fix

Moved deleted proctoring event route to deletes/ folder.

src/modules/questions/actions.ts

@@ -4,7 +4,7 @@ import { requirePermission, PermissionDeniedError } from "@/shared/lib/auth-guar
 import { Permissions } from "@/shared/types/permissions";
 import { CreateQuestionSchema } from "./schema";
 import type { CreateQuestionInput } from "./schema";
-import { ActionState } from "@/shared/types/action-state";
+import type { ActionState } from "@/shared/types/action-state";
 import { revalidatePath } from "next/cache";
 import { z } from "zod";
 import {
@@ -17,6 +17,12 @@ import {
 } from "./data-access";
 import type { KnowledgePointOption } from "./types";
 
+/** Result type of getQuestions (data + meta) */
+type QuestionsListResult = Awaited<ReturnType<typeof getQuestions>>;
+
+/** Result type of getKnowledgePointOptions */
+type KnowledgePointOptionsResult = KnowledgePointOption[];
+
 export async function createNestedQuestion(
   prevState: ActionState<string> | undefined,
   formData: FormData | CreateQuestionInput
@@ -151,26 +157,34 @@ export async function deleteQuestionAction(
   }
 }
 
-export async function getQuestionsAction(params: GetQuestionsParams) {
+export async function getQuestionsAction(
+  params: GetQuestionsParams
+): Promise<ActionState<QuestionsListResult>> {
   try {
     await requirePermission(Permissions.QUESTION_READ);
-    return await getQuestions(params);
+    const data = await getQuestions(params);
+    return { success: true, data };
   } catch (e) {
     if (e instanceof PermissionDeniedError) {
-      throw e;
+      return { success: false, message: e.message };
     }
-    throw e;
+    const message = e instanceof Error ? e.message : "Failed to fetch questions";
+    return { success: false, message };
   }
 }
 
-export async function getKnowledgePointOptionsAction(): Promise<KnowledgePointOption[]> {
+export async function getKnowledgePointOptionsAction(): Promise<
+  ActionState<KnowledgePointOptionsResult>
+> {
   try {
     await requirePermission(Permissions.QUESTION_READ);
-    return await getKnowledgePointOptions();
+    const data = await getKnowledgePointOptions();
+    return { success: true, data };
   } catch (e) {
     if (e instanceof PermissionDeniedError) {
-      throw e;
+      return { success: false, message: e.message };
     }
-    throw e;
+    const message = e instanceof Error ? e.message : "Failed to fetch knowledge point options";
+    return { success: false, message };
   }
 }