url: restrict file paths regex to one slash (#7355)

Fixes https://github.com/ghostty-org/ghostty/discussions/7351.

This restricts the valid path prefixes to prevent false matches caused
by literal dot.

src/config/url.zig

@@ -26,7 +26,7 @@ pub const regex =
     "(?:" ++ url_schemes ++
     \\)(?:
     ++ ipv6_url_pattern ++
-    \\|[\w\-.~:/?#@!$&*+,;=%]+(?:[\(\[]\w*[\)\]])?)+(?<![,.])|(?:\.\.\/|\.\/*|\/)[\w\-.~:\/?#@!$&*+,;=%]+(?:\/[\w\-.~:\/?#@!$&*+,;=%]*)*
+    \\|[\w\-.~:/?#@!$&*+,;=%]+(?:[\(\[]\w*[\)\]])?)+(?<![,.])|(?:\.\.\/|\.\/|\/)[\w\-.~:\/?#@!$&*+,;=%]+(?:\/[\w\-.~:\/?#@!$&*+,;=%]*)*
     ;
 const url_schemes =
     \\https?://|mailto:|ftp://|file:|ssh:|git://|ssh://|tel:|magnet:|ipfs://|ipns://|gemini://|gopher://|news:
@@ -112,6 +112,10 @@ test "url regex" {
             .input = "url with dashes [mode 2027](https://github.com/contour-terminal/terminal-unicode-core) for better unicode support",
             .expect = "https://github.com/contour-terminal/terminal-unicode-core",
         },
+        .{
+            .input = "dot.http://example.com",
+            .expect = "http://example.com",
+        },
         // weird characters in URL
         .{
             .input = "weird characters https://example.com/~user/?query=1&other=2#hash and more",