feat: Autocreate missing PTRs, handle notFound errors gracefully

[fust]

When CreatePTR is enabled, an A record update would fail if the corresponding PTR record had been deleted or never existed in Infoblox, causing a reconciliation loop with no recovery. This change detects that scenario and creates the missing PTR instead of trying to update a non-existent record.

Additionally, notFound errors from Infoblox were previously silently swallowed in recordSet, incrementing the failed API call counter and making it impossible to distinguish a missing record from a real error in logs or metrics.
Errors are now wrapped with contextual record info before the notFound check, so notFound is treated as an expected condition (no counter bump, no early return) while other errors are still surfaced.
A minor metric label bug ("GetObject" on the create path) and action error logging in submitChanges are also fixed.