fix: don't fail the whole SBOM when a cataloger panics on one file (#5342)

* fix(generic): recover from parser and processor panics

- a panic while parsing one file becomes an unknown for that location instead of failing the whole SBOM
- a panic in a package processor is logged as a warning and the unprocessed results are kept
- stacks go to the trace log, not into the unknown text

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* fix(unknown): keep errors that unwrap to nil

`sync.PanicError` with a non-error panic value (e.g. `panic("boom")`) unwraps to nil, and was being dropped entirely from the error graph instead of being kept as a leaf.

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* fix(task): don't put the stack trace in task panic errors

Task panics are still fatal, but the error now reads `panic in task "<name>": <value>` and the stack goes to the debug log.

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* test(generic): cover chained processors when a later one panics

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* fix(file): recover from panics in the executable and file digest catalogers

A panic while reading one file is now recorded as an unknown for that file instead of failing the whole SBOM, the same as generic catalogers.

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

---------

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

internal/task/executor.go

@@ -51,7 +51,8 @@ func runTaskSafely(ctx context.Context, t Task, resolver file.Resolver, s sbomsy
 	// handle individual cataloger panics
 	defer func() {
 		if e := recover(); e != nil {
-			err = fmt.Errorf("%v at:\n%s", e, string(debug.Stack()))
+			log.WithFields("task", t.Name()).Debugf("task panic stack:\n%s", debug.Stack())
+			err = fmt.Errorf("panic in task %q: %v", t.Name(), e)
 		}
 	}()