Test: add additional edge cases for uri format across active drafts

[severe77]

Summary

Adds additional boundary edge cases for the uri format across active drafts (draft3 through draft2020-12).

What’s included

The new cases focus on:

• Invalid percent-encoding sequences (non-hex digits, incomplete triplets, lone %)
• Invalid scheme syntax (non-letter start, disallowed characters)
• Non-numeric port values

These cases align with the generic URI syntax defined in RFC 3986 (§2.1, §3.1, and §3.2.3).

Scope

• Applied consistently to all active drafts that define format: "uri"
• No existing tests were modified

[severe77]

@jdesrosiers @karenetheridge hey just a quick confirmation.
I applied these additions to draft3 through draft2020-12.
I left v1 unchanged since these cases relate to stricter RFC boundary behavior.

Would you prefer that similar cases also be added to v1 for consistency?