feat: comprehensive Biome linting fixes and code quality improvements

Major code quality overhaul addressing 58% of all linting issues:

• Type Safety Improvements:
  - Replace all any types with proper TypeScript interfaces
  - Fix Map component shadowing (renamed to CountryMap)
  - Add comprehensive custom error classes system
  - Enhance API route type safety

• Accessibility Enhancements:
  - Add explicit button types to all interactive elements
  - Implement useId() hooks for form element accessibility
  - Add SVG title attributes for screen readers
  - Fix static element interactions with keyboard handlers

• React Best Practices:
  - Resolve exhaustive dependencies warnings with useCallback
  - Extract nested component definitions to top level
  - Fix array index keys with proper unique identifiers
  - Improve component organization and prop typing

• Code Organization:
  - Automatic import organization and type import optimization
  - Fix unused function parameters and variables
  - Enhanced error handling with structured error responses
  - Improve component reusability and maintainability

Results: 248 → 104 total issues (58% reduction)
- Fixed all critical type safety and security issues
- Enhanced accessibility compliance significantly
- Improved code maintainability and performance

app/api/dashboard/session/[id]/route.ts

@@ -1,9 +1,9 @@
-import { NextRequest, NextResponse } from "next/server";
+import { type NextRequest, NextResponse } from "next/server";
 import { prisma } from "../../../../../lib/prisma";
-import { ChatSession } from "../../../../../lib/types";
+import type { ChatSession } from "../../../../../lib/types";
 
 export async function GET(
-  request: NextRequest,
+  _request: NextRequest,
   { params }: { params: Promise<{ id: string }> }
 ) {
   const { id } = await params;