`misc`: update `.clang-format`

[WillemKauf]

Makes the following changes to .clang-format to ensure consistent formatting in the codebase:

+ PointerAlignment: Left
+ QualifierAlignment: Custom
+ QualifierOrder: [static, inline, const, type]
+ ReferenceAlignment: Left

Thereby enforcing west const, pointer/reference alignment to the type, and a consistent qualifier order for all .cc/.h files.

As noted by https://clang.llvm.org/docs/ClangFormatStyleOptions.html#qualifieralignment, extra care should be taken when reviewing formatting performed with this option.

Backports Required

• [X] none - not a bug fix
• [ ] none - this is a backport
• [ ] none - issue does not exist in previous branches
• [ ] none - papercut/not impactful enough to backport
• [ ] v24.2.x
• [ ] v24.1.x
• [ ] v23.3.x

Release Notes

• none

[WillemKauf]

Force push to:

• Correct improper syntax from concept const auto& -> const concept auto& in security/jwt.h

[vbotbuildovich]

ducktape was retried in https://buildkite.com/redpanda/redpanda/builds/53606#0191944b-2084-47d1-af16-6f4cb6199042

ducktape was retried in https://buildkite.com/redpanda/redpanda/builds/54401#0191e724-5e61-477d-a6ae-5a1b71fc573a

ducktape was retried in https://buildkite.com/redpanda/redpanda/builds/54601#019200f2-5d95-46f2-9c88-0d7ec0e8e5a3

[WillemKauf]

Moved to draft mode to prevent merging before Friday at @andijcr's request.

[bashtanov]

Do you have an example (or even an overview?) of how QualifierAlignment can spoil the code?

[andijcr]

Do you have an example (or even an overview?) of how QualifierAlignment can spoil the code?

apparently with concept

void foo(conceptable auto const&);

gets transformed to

void foo(conceptable const auto&);

and this doesn't compile. the correct transformation is

void foo(const conceptable auto&);

but i guess it's just a bug in the formatted. i don't know if there are valid cases where const position cal lead to valid but not correct code

[oleiman]

a bug in the formatter

Ya, as I understand it, clang-format doesn't do a full parse, so distinguishing between lexically similar but semantically distinct expressions is pretty hard. Maybe that's not a bug; more of a fundamental limitation?

[WillemKauf]

Do you have an example (or even an overview?) of how QualifierAlignment can spoil the code?

Unfortunately the clang-format docs aren't specific by what they mean by this, but the one compiler error I saw as a result of setting this property was as Andrea pointed out (the example with a conceptable const auto variable).

[dotnwat]

lgtm, approved in case we want to move forward with this instead of clang-format 18

we are going to move to clang-format-18

[bashtanov]

Unfortunately the clang-format docs aren't specific by what they mean by this, but the one compiler error I saw as a result of setting this property was as Andrea pointed out (the example with a conceptable const auto variable).

TBH I'd not use formatter settings that may convert buildable code into non-buildable

[dotnwat]

for the alignment changes where our clang-format settings currently has no preference and will keep the alignment unchanged, you could drip the changes into the tree over a series of PRs that kept review cost minimal.

i think that's only actually important for we are afraid that clang-format is making some kind of "incorrect" change?

[vbotbuildovich]

new failures in https://buildkite.com/redpanda/redpanda/builds/54601#019200f2-5d95-46f2-9c88-0d7ec0e8e5a3:

"rptest.tests.usage_test.UsageTestCloudStorageMetrics.test_usage_manager_cloud_storage"
"rptest.tests.acls_test.AccessControlListTestUpgrade.test_describe_acls.use_tls=True.use_sasl=False.enable_authz=None.authn_method=none.client_auth=True"
"rptest.tests.acls_test.AccessControlListTestUpgrade.test_describe_acls.use_tls=True.use_sasl=False.enable_authz=None.authn_method=None.client_auth=True"
"rptest.tests.acls_test.AccessControlListTestUpgrade.test_describe_acls.use_tls=True.use_sasl=True.enable_authz=False.authn_method=none.client_auth=True"
"rptest.tests.acls_test.AccessControlListTestUpgrade.test_describe_acls.use_tls=True.use_sasl=True.enable_authz=None.authn_method=none.client_auth=True"
"rptest.tests.archival_test.ArchivalTest.test_write.cloud_storage_type_and_url_style=.CloudStorageType.ABS.2.virtual_host"
"rptest.tests.node_id_assignment_test.NodeIdAssignment.test_rejoin_after_decommission"
"rptest.tests.pandaproxy_test.PandaProxyMTLSTest.test_mtls"

new failures in https://buildkite.com/redpanda/redpanda/builds/54601#019200f2-5d92-46a4-983d-735710421faa:

"rptest.tests.cloud_storage_scrubber_test.CloudStorageScrubberTest.test_scrubber.cloud_storage_type=CloudStorageType.ABS"