Make unknown/renamed/removed lints passed via command line respect lint levels

[weihanglo]

What does this PR try to resolve?

This is the implementation of MCP rust-lang/compiler-team#667.

Also fixes #74722

How should we test and review this PR?

• The first commit demonstrates the current behavior.
• The second moves code without any behavior change.
• The last commit is the meaty part of the MCP, including UI snapshot changes.

Additional information

A bit unfortunate this brings some diagnostic duplications. I am not familiar enough with the codebase to eliminiate them. Will appreciate if someone can give pointers. (Or, we can defer this to follow-up PRs?)

[rustbot]

r? @petrochenkov

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[weihanglo]

r? @estebank

If you've got time to review this :)

[oli-obk]

@bors r+

[bors]

📌 Commit a11805a has been approved by oli-obk

It is now in the queue for this repository.

[bors]

⌛ Testing commit a11805a with merge 5d62ab8...

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 5d62ab8 to master...

[rust-timer]

Finished benchmarking commit (5d62ab8): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.4%	[1.2%, 1.6%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.5%	[0.5%, 0.5%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.6%	[-3.5%, -1.6%]	3
All ❌✅ (primary)	-	-	0

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 630.224s -> 629.427s (-0.13%)
Artifact size: 317.56 MiB -> 317.62 MiB (0.02%)