fix(functions): resolve deno lint errors in generated edge function template

[7ttp]

Fix: Remove inline jsr: import from generated functions template

The template created by supabase functions new currently triggers Deno lint errors because it includes an inline jsr: import without a version:

import "jsr:@supabase/functions-js/edge-runtime.d.ts";

This violates two default Deno lint rules:

• no-import-prefix – inline jsr: dependencies are not allowed
• no-unversioned-import – missing version in specifier

Changes in this PR

• Moves the @supabase/functions-js type dependency into deno.json with a pinned version
• Updates index.ts to use a bare specifier import, following Deno’s recommended pattern

These updates resolve the lint errors and ensure the generated functions template adheres to Deno best practices.

Closes https://github.com/supabase/cli/issues/4424