chore: add pre-commit hooks, tighten ESLint, activate Sentry DSN, publish CI coverage (Phase 1)

- Install husky v9 + lint-staged: pre-commit runs eslint --fix and prettier on staged files
- Tighten ESLint base config: no-console→error, ban-ts-comment (ts-ignore banned, ts-expect-error with description allowed), reportUnusedDisableDirectives→error
- Migrate web app from deprecated `next lint` to `eslint src/` with flat config and react-hooks plugin
- Convert all 5 @ts-ignore to @ts-expect-error with descriptions, remove stale disable comments
- Add NEXT_PUBLIC_SENTRY_DSN to docker-compose.prod.yml and .env.example
- Add coverage artifact upload step to CI test job
- Pre-existing violations (102 warnings) downgraded to warn in web config for Phase 2 cleanup

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

apps/web/src/app/api/sse/timeline/route.ts

@@ -2,7 +2,8 @@ import { loadRoleDefaults } from "@capakraken/api";
 import { deriveUserSseSubscription, eventBus } from "@capakraken/api/sse";
 import { startReminderScheduler } from "@capakraken/api/lib/reminder-scheduler";
 import { prisma } from "@capakraken/db";
-import { SSE_EVENT_TYPES, SystemRole, type PermissionOverrides } from "@capakraken/shared";
+import type { SystemRole } from "@capakraken/shared";
+import { SSE_EVENT_TYPES, type PermissionOverrides } from "@capakraken/shared";
 import { auth } from "~/server/auth.js";
 
 export const dynamic = "force-dynamic";
@@ -59,26 +60,27 @@ export async function GET() {
     start(controller) {
       // Send initial connection confirmation
       controller.enqueue(
-        encoder.encode(`data: ${JSON.stringify({ type: SSE_EVENT_TYPES.PING, timestamp: new Date().toISOString() })}\n\n`),
+        encoder.encode(
+          `data: ${JSON.stringify({ type: SSE_EVENT_TYPES.PING, timestamp: new Date().toISOString() })}\n\n`,
+        ),
       );
 
       // Subscribe to event bus
-      const unsubscribe = eventBus.subscribe(
-        (event) => {
-          try {
-            controller.enqueue(encoder.encode(`data: ${JSON.stringify(event)}\n\n`));
-          } catch {
-            // Client disconnected
-          }
-        },
-        subscription,
-      );
+      const unsubscribe = eventBus.subscribe((event) => {
+        try {
+          controller.enqueue(encoder.encode(`data: ${JSON.stringify(event)}\n\n`));
+        } catch {
+          // Client disconnected
+        }
+      }, subscription);
 
       // Heartbeat every 30 seconds
       const heartbeat = setInterval(() => {
         try {
           controller.enqueue(
-            encoder.encode(`data: ${JSON.stringify({ type: SSE_EVENT_TYPES.PING, timestamp: new Date().toISOString() })}\n\n`),
+            encoder.encode(
+              `data: ${JSON.stringify({ type: SSE_EVENT_TYPES.PING, timestamp: new Date().toISOString() })}\n\n`,
+            ),
           );
         } catch {
           clearInterval(heartbeat);