fix: preserve query string in config.options when parsing connection URL

[mujib77]

Problem

When parsing a PostgreSQL connection URL with query parameters
(e.g. ?schema=public&ssl=true), the parser spreads each param
directly onto the config object but never preserves the raw query
string in config.options.

This breaks code that expects config.options to contain the
original query string — for example, when reconstructing connection
URLs or implementing SSH tunneling.

Fixes #3418

Solution

After parsing search params, save the raw query string to
config.options if it exists:

if (result.search) {
  config.options = result.search.slice(1)
}

Test

Manually verified that parsing a URL with query params now
correctly populates config.options.