Evaluate and enable new linters in golangci-lint 1.62.2

[mstoykov]

After #4095 the following three new linters are available:

• recvcheck - seems useful as it checks we do not mix receiver types, which sometimes might mean bugs.
• iface - seems like a good idea
• filen - length of files in this one seem to be incredibly low for our cases and I am not certain file length is good indicator of anything

Unfortuantely recvcheck got a screen of errors when enabled, which might mean problems, but it also means more work to enable it - so I am openning an issue.