Increase multi_get default maxBytes

[fa1k3]

Summary

Raises the default multi_get size limit from 10KB to 64KB.

Why

The previous 10KB default skips fairly normal documentation/wiki pages unless callers know to override maxBytes. A 64KB default is still conservative, but covers more typical long-form docs without changing the explicit maxBytes override behavior.

Changes

• Change DEFAULT_MULTI_GET_MAX_BYTES to 64 * 1024.
• Use that shared constant in the MCP multi_get input schema instead of repeating a literal default.
• Update CLI help and docs to show the 64KB default.
• Add a regression test proving default multi_get no longer skips a normal wiki-sized file, while explicit low maxBytes still skips large files.

Tests

• npm run build
• npm run test:types
• npm run test:node -- test/mcp.test.ts — 58 passed
• npm run test:node — 892 passed
• npm run test:bun — 892 passed