Frontend half of removing hive-level agent spawning (swarm-level
creation now covers it, and its forge-works confirmation just landed
in hive/hive-chat). Removes call.js's blank-name spawn-request form
(R3QU3ST SP4WN) and its now-orphaned .spawnform CSS.
Deliberately keeps core.js's tombstone-list revive action (R3V1V3) --
a different feature (respawn an *existing* agent, reusing its kept
state), not agent creation, and not what this issue asked to remove.
It happens to post to the same /api/request-spawn action with the
tombstone's own name pre-filled rather than a blank input.
Backend endpoint + wiring is a separate slice (damocles).