fix: replace context.TODO() with context.Background() in 6 fire-and-forget call sites

[KorsarOfficial]

Closes #95

Semantic analysis

context.TODO() and context.Background() are both non-nil, non-cancellable root contexts, but carry different intent signals:

	context.TODO()	context.Background()
Documented meaning	Placeholder — decision deferred	Correct root context for background/startup
Static analysis tools	Flag as "unresolved"	Clean
Code review signal	"we don't know yet"	"intentional root context"

Only sites where Background() is the final correct choice are changed. Sites with // TODO: this context should be tied to e.g. Run() duration are intentionally left as context.TODO() — the placeholder semantics are correct there.

Files changed (6)

File	Location
agent/collector/pkg/dso/map.go	ccache onDelete callback (no parent context available)
agent/collector/pkg/dso/parser/parser.go	constructor log statement
internal/binaryprocessor/binaryprocessor.go	constructor initialization
pkg/kafka/producer/producer.go	Kafka producer constructor
pkg/profile_event/signal_profile_processor/service.go	service constructor
pkg/s3/http_proxy.go	proxy after updater shutdown

Δ logic = 0. Mechanical substitution only at sites where the intent is unambiguous.

[KorsarOfficial]

📄 Full analysis report (PDF): 08-perforator-optimizations.pdf

Covers complexity analysis, concurrency audit, and verification for all 7 optimizations.

[MikailBag]

I can't agree that using empty context is right in any of these cases.

For logging it looses key-value pairs, for cancellation is causes goroutine leaks (incl. in tests).