Replace nanorouter's regex+decodeURI normalization with the WHATWG URL
parser. Path segments are percent-decoded exactly once in the trie, with
a keep-raw fallback instead of the URIError that crashed v7 on a literal
'%'. Route definitions and locations are NFC-normalized so 'café' matches
regardless of composition. Hash-to-slash rewriting now handles every hash,
not just the first, and state.href is decoded for humans (raw on failure).
Behavior changes from v7: params are no longer double-decoded (%2540 →
'%40', not '@'), and unmatchable encodings fall back to raw segments
instead of silently 404ing.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014NgfSjHE11oFpoSnLVKLXd
