docs: reorganize configuration files

[ldez]

Reorganize the configuration references (and the configuration) to improve readability.

Before:

• run
• output
• linters-settings
• linters
• issues
• severity

After:

• linters
• linters-settings
• issues
• output
• run
• severity

[bombsimon]

Having linters before linters settings sounds very reasonable although for me personally I think general golangci-lint specific configuration starting at LOC 2000 is very far down and that linters and linters setting should come last.

But it's not a very strong opinion so go for it!

[ldez]

My logic was "new user" related:

• first, you choose your linters
• then you configure linters
• then you apply exclusions
• then you customize the output
• then you increase your timeout
• then you don't use severities 😸

But each section will still be split inside the doc of the configuration https://golangci-lint.run/usage/configuration/

So this has just a light impact.

[bombsimon]

• then you don't use severities 😸

Haha, this one was the best one!

I get your reasoning around adding and configuring linters, linters settings and exclusions first. And for proper documentation I don't think reading the reference config with thousands of lines is the best anyway.