Support (and ignore) ‘tool’ directive in go.mod files. (#2064)

See https://go.dev/doc/modules/gomod-ref#tool and
https://go.dev/doc/go1.24#tools.

Fixes #2031

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**What type of PR is this?**

Feature

**What package or component does this PR mostly affect?**

all

**What does this PR do? Why is it needed?**

Don't fail parsing of go.mod if it contains a tool directive.

**Which issues(s) does this PR fix?**

Fixes #2031
2 files changed