Adds apply_job_task_count() to overwrite a standalone primary resreq's
minTasks/maxTasks with a job's real requested task count, no-op for
COMPOUND/ALTER nested primaries, with a defensive min>max clamp.
Closes the gap that lets scheduler-allocation's multi-host allocator
ever be reached (bug-1770). Wiring at live ingest call sites follows
in subsequent tasks.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XYdtrEWWZfKRRGED7raEYg
