fix: Resolve all ESLint errors and warnings in web package

Fixes all 542 ESLint problems in the web package to achieve 0 errors and 0 warnings.

Changes:
- Fixed 144 issues: nullish coalescing, return types, unused variables
- Fixed 118 issues: unnecessary conditions, type safety, template literals
- Fixed 79 issues: non-null assertions, unsafe assignments, empty functions
- Fixed 67 issues: explicit return types, promise handling, enum comparisons
- Fixed 45 final warnings: missing return types, optional chains
- Fixed 25 typecheck-related issues: async/await, type assertions, formatting
- Fixed JSX.Element namespace errors across 90+ files

All Quality Rails violations resolved. Lint and typecheck both pass with 0 problems.

Files modified: 118 components, tests, hooks, and utilities

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

apps/web/src/lib/api/teams.ts

@@ -153,14 +153,17 @@ export const mockTeams: Team[] = [
  * Mock team with members for development
  */
 const baseTeam = mockTeams[0];
+if (!baseTeam) {
+  throw new Error("Mock team not found");
+}
 export const mockTeamWithMembers: TeamWithMembers = {
-  id: baseTeam!.id,
-  workspaceId: baseTeam!.workspaceId,
-  name: baseTeam!.name,
-  description: baseTeam!.description,
-  metadata: baseTeam!.metadata,
-  createdAt: baseTeam!.createdAt,
-  updatedAt: baseTeam!.updatedAt,
+  id: baseTeam.id,
+  workspaceId: baseTeam.workspaceId,
+  name: baseTeam.name,
+  description: baseTeam.description,
+  metadata: baseTeam.metadata,
+  createdAt: baseTeam.createdAt,
+  updatedAt: baseTeam.updatedAt,
   members: [
     {
       teamId: "team-1",