fix(install): suppress peer dependency warnings for overridden packages (#34935)
When a package is pinned through the root package.json "overrides"
field, Deno still emitted a peer dependency mismatch warning for it, even
though the override is the user explicitly choosing that version. The warning
was computed purely from the declared peer range versus the resolved
version, with no awareness of overrides, so there was no way to silence it short
of removing the override.
This treats an override as an authoritative resolution directive: when a
package has a matching entry in "overrides", its peer dependency
mismatch is intentional and is no longer reported. Mismatches for packages that
are not overridden continue to warn as before. The filtering happens at the
single point where the diagnostics are displayed, which already has
access to the parsed overrides via the version resolver.
Closes #32801