Create AbortSignal without JS

[Jarred-Sumner]

What does this PR do?

Micro-optimize AbortSignal a little

• Slightly reduce memory usage of AbortSignal by setting the inline capacity of the Vector used within to 2 instead of the default of 6
• Instead of creating a JS object for AbortSignal, we can create the C++ one and lazily create the GC'd version

How did you verify your code works?

Existing tests

[github-actions]

❌ @Jarred-Sumner 5 files with test failures on linux-x64-baseline:

• test/cli/install/bun-install.test.ts
• test/js/node/watch/fs.watch.test.ts
• test/js/third_party/mongodb/mongodb.test.ts
• test/js/third_party/postgres/postgres.test.ts
• test/js/third_party/prisma/prisma.test.ts

View test output

^{#702bc037e382fcf2de0edae8f447ba21086a019e}

[github-actions]

❌ @Jarred-Sumner 10 files with test failures on bun-darwin-aarch64:

• test/cli/install/bun-install.test.ts
• test/integration/next/default-pages-dir/test/dev-server.test.ts
• test/js/bun/spawn/spawn.test.ts
• test/js/bun/test/test-test.test.ts
• test/js/bun/util/filesink.test.ts
• test/js/node/dns/node-dns.test.js
• test/js/node/watch/fs.watch.test.ts
• test/js/third_party/mongodb/mongodb.test.ts
• test/js/third_party/postgres/postgres.test.ts
• test/js/third_party/prisma/prisma.test.ts

View test output

^{#702bc037e382fcf2de0edae8f447ba21086a019e}

[github-actions]

❌ @Jarred-Sumner 7 files with test failures on linux-x64:

• test/cli/install/bun-install.test.ts
• test/integration/next/default-pages-dir/test/next-build.test.ts
• test/js/bun/util/filesink.test.ts
• test/js/node/watch/fs.watch.test.ts
• test/js/third_party/mongodb/mongodb.test.ts
• test/js/third_party/postgres/postgres.test.ts
• test/js/third_party/prisma/prisma.test.ts

View test output

^{#702bc037e382fcf2de0edae8f447ba21086a019e}

[github-actions]

❌ @Jarred-Sumner 10 files with test failures on bun-darwin-x64-baseline:

• test/cli/install/bun-install.test.ts
• test/js/bun/spawn/spawn.test.ts
• test/js/bun/util/filesink.test.ts
• test/js/node/fs/fs.test.ts
• test/js/node/os/os.test.js
• test/js/third_party/mongodb/mongodb.test.ts
• test/js/third_party/postgres/postgres.test.ts
• test/js/third_party/prisma/prisma.test.ts
• test/js/third_party/webpack/webpack.test.ts
• test/js/web/timers/setTimeout.test.js

View test output

^{#702bc037e382fcf2de0edae8f447ba21086a019e}