Add a Linter to Detect Defer Calls in For Loop

[rauljordan]

Resolves NIT-4439

A common pitfall in Go development are bugs arising from defer invocations in for loops, which we are best avoiding. This adds a linter with tests

[codecov]

Codecov Report

❌ Patch coverage is 0% with 56 lines in your changes missing coverage. Please review.
✅ Project coverage is 34.10%. Comparing base (976ea45) to head (f666318).
⚠️ Report is 43 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4616   +/-   ##
=======================================
  Coverage   34.09%   34.10%           
=======================================
  Files         497      498    +1     
  Lines       59155    59194   +39     
=======================================
+ Hits        20169    20188   +19     
- Misses      35434    35463   +29     
+ Partials     3552     3543    -9     

[github-actions]

❌ 11 Tests Failed:

Tests completed	Failed	Passed	Skipped
4748	11	4737	0

View the top 3 failed tests by shortest run time

TestAliasingFlaky

Stack Traces | -0.000s run time

=== RUN   TestAliasingFlaky
=== PAUSE TestAliasingFlaky
=== CONT  TestAliasingFlaky
    common_test.go:777: BuildL1 deployConfig: DeployBold=true, DeployReferenceDAContracts=false
INFO [04-08|20:24:46.578] Starting peer-to-peer node               instance=test-stack-name/linux-amd64/go1.25.8
WARN [04-08|20:24:46.578] P2P server will be useless, neither dialing nor listening
INFO [04-08|20:24:46.579] Submitted contract creation              hash=0x399184f9977f0f6ea1e1f807698efdd88b4fcbb85106214486ecbfdf28b60683 from=0x57Ff0F473737a1c161bfF9efDF016F7991585088 nonce=0  contract=0xA46C59ce2FCaF445F96f66F0411e06A94D34BF45 value=0
WARN [04-08|20:24:46.580] Served eth_getTransactionReceipt         reqid=7 duration="30.928µs" err="transaction indexing is in progress" errdata="\"transaction indexing is in progress\""
INFO [04-08|20:24:46.580] Starting work on payload                 id=0x03486db7e7dc4073
INFO [04-08|20:24:46.580] New local node record                    seq=1,775,679,886,580 id=168376716c3f8def                        ip=127.0.0.1 udp=0 tcp=0
INFO [04-08|20:24:46.580] Started P2P networking                   self=enode://aad074ed4991ca4e36d5ec675eba345a6b56b9ae99e1aa076297f76b2224ca117390ad2d08505199942f23fdb1330de68223e0ce2e529270d475433000ce4367@127.0.0.1:0
WARN [04-08|20:24:46.580] Getting file info                        dir= error="stat : no such file or directory"

TestPruningDBSizeReduction

Stack Traces | 0.000s run time

=== RUN   TestPruningDBSizeReduction
--- FAIL: TestPruningDBSizeReduction (0.00s)

TestBatchPosterL1SurplusMatchesBatchGasFlaky

Stack Traces | 0.550s run time

... [CONTENT TRUNCATED: Keeping last 20 lines]
panic: runtime error: invalid memory address or nil pointer dereference [recovered, repanicked]
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x20f3452]

goroutine 23 [running]:
testing.tRunner.func1.2({0x3866aa0, 0x62fc9b0})
	/opt/hostedtoolcache/go/1.25.8/x64/src/testing/testing.go:1872 +0x237
testing.tRunner.func1()
	/opt/hostedtoolcache/go/1.25.8/x64/src/testing/testing.go:1875 +0x35b
panic({0x3866aa0?, 0x62fc9b0?})
	/opt/hostedtoolcache/go/1.25.8/x64/src/runtime/panic.go:783 +0x132
github.com/offchainlabs/nitro/arbnode.(*InboxTracker).GetBatchCount(0x17171900?)
	/home/runner/work/nitro/nitro/arbnode/inbox_tracker.go:210 +0x12
github.com/offchainlabs/nitro/arbnode.(*InboxTracker).FindInboxBatchContainingMessage(0x0, 0x6)
	/home/runner/work/nitro/nitro/arbnode/inbox_tracker.go:225 +0x2f
github.com/offchainlabs/nitro/system_tests.TestBatchPosterL1SurplusMatchesBatchGasFlaky(0xc000400fc0)
	/home/runner/work/nitro/nitro/system_tests/batch_poster_test.go:839 +0x725
testing.tRunner(0xc000400fc0, 0x4242560)
	/opt/hostedtoolcache/go/1.25.8/x64/src/testing/testing.go:1934 +0xea
created by testing.(*T).Run in goroutine 1
	/opt/hostedtoolcache/go/1.25.8/x64/src/testing/testing.go:1997 +0x465

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