Fix before_all filters running twice

[sdogruyol]

Fixes #757

Problem

After #737, global filters lived in the radix tree alongside path-specific ones. call_block_for_path_type ran the * filters explicitly, then the radix lookup for the request path matched the same * catch-all again — so before_all blocks ran twice per request (duplicated DB/auth calls).

A related edge case: before_all "/*" registers on a different key than before_all, so / could miss the global filter entirely when another wildcard filter (e.g. before_all "/api/*") was also registered.

Solution

Make duplicate execution structurally impossible by separating global filters from the radix tree at registration time:

• _add_route_filter normalizes "*" and "/*" into a dedicated @global_filters hash — they never enter the radix tree
• call_block_for_path_type simply runs global filters first, then the radix lookup for path-specific filters; the lookup can no longer re-match a global filter
• before_all "/*" now behaves exactly like before_all, including on /

No dedup bookkeeping or per-request allocations needed.