Adds docs/server/resources.md as the first page under the planned
docs/server/ directory. Covers static resources, RFC 6570 template
patterns, the built-in security checks and how to relax them, the
safe_join pattern for filesystem handlers, and equivalent patterns for
low-level Server implementations.
Creates the docs/server/ nav section in mkdocs.yml.
Max Isbey
a5afb9892b