Go: Model `log/slog` as a logging sink by sauyon · Pull Request #22004 · github/codeql

The standard-library structured logger `log/slog` (Go 1.21+) was not
modeled, so `go/log-injection` and `go/clear-text-logging` were blind to
any code that logs through it.

Model its logging functions and `*slog.Logger` methods — `Debug`, `Info`,
`Warn`, `Error`, their `Context` variants, and `Log`/`LogAttrs` — as
`log-injection` sinks (the kind that feeds `LoggerCall`, powering both
queries). Adds `log/slog` cases to the `LoggerCall` library test.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Copilot review on github#22004: the Log/LogAttrs test cases didn't pass any
variadic args/attrs, so the Argument[..3] portion of the sink range was
untested. Pass an ...any arg to slog.Log/Logger.Log and a slog.Attr to
slog.LogAttrs/Logger.LogAttrs, with inline expectations asserting they're
captured as logged components.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>