Brings the project to a clean `make lint` baseline (0 issues).
Mechanical:
- Wrap deferred resp.Body.Close() in closures (router/discovery.go,
router/probe.go) so the unchecked return surfaces as `_ = ...`.
- Apply `_ = ...` (single or multi-return blank) to test-file calls
that intentionally ignore errors: os.MkdirAll / os.WriteFile / os.Chdir
in setup paths, Close / Shutdown in teardown, Submit / Spawn / Send /
LoadDir in tests that assert on side effects.
Structural:
- engine.handleRequestTooLarge drops the unused req parameter and
rebuilds the request from compacted history (SA4009 — argument was
overwritten before first use).
- provider.ClassifyHTTPStatus and google.applyCapabilityOverrides switch
to tagged switches over the discriminator (QF1002).
- tui.app.go MouseWheel + inputMode and cmd/gnoma main slm-status use
tagged switches in place of equality chains (QF1003).
- cmd/gnoma main.go merges a var decl with its immediate assignment
(S1021).
- Three empty-branch sites (dispatcher_test, loader_test,
coordinator_test) become real assertions or get the dead `if` removed
(SA9003).
vikingowl