Each logger that writes to a file spawns a lumberjack goroutine for
log rotation. With ~30 loggers writing to /var/log/stackrox/log.txt,
that's 30 idle goroutines + 30 independent file handles to the same
file. In container environments, logs go to stdout and are collected
by the container runtime — file logging is unnecessary overhead.

Set ROX_LOGGING_TO_FILE=false to disable file logging, saving:
- 30 goroutines and their stacks
- File I/O overhead
- lumberjack rotation processing

Default is true (unchanged behavior) for backward compatibility.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Each CreateLogger call created an independent lumberjack.Logger for
the same log file, spawning its own rotation goroutine. With ~30
loggers, that's 30 goroutines + 30 file handles to the same file.

Share a single writer per path via a map. This reduces log rotation
goroutines from 30 to 1 and eliminates potential corruption from
concurrent uncoordinated writes to the same file.

GC sweet spot experiment findings (included in commit message for context):
- 128Mi: GC thrashing (84 GC/min, 200m CPU)
- 160Mi: Sweet spot (2 GC/min, 4m CPU)
- 192Mi: Comfortable (0 GC/min, 3m CPU)
- Rule: set limit to 1.3-1.5x natural heap size

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Process enrichment LRU cache was hardcoded at 100K entries — designed
for large enterprise clusters with thousands of containers. On a
50-container edge cluster, this is 2000x oversized.

Use pkg/sensor/queue.ScaleSize to scale based on ROX_MEMLIMIT:
- 128Mi limit → ~3K entries (sufficient for 50 containers)
- 4Gi limit → 100K entries (unchanged behavior)
- Minimum: 100 entries

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>