soul: per-tick arena bracketing in awareness_run + hand-patched dist/soul.c

awareness_run's while-loop ran outside any request arena, so every
allocation in every 1s tick (search JSON, heartbeat payloads, curiosity
activations) was treated as permanent by the runtime — 7.5GB RSS in
under a minute. Bracket each iteration with el_arena_push/el_arena_pop
(same pattern the compiler emits for scoped blocks; state_set/state_get
persist separately via el_strdup_persist and are unaffected).

dist/soul.c carries the same change hand-patched at the compiled
awareness_run site — elc is currently unsafe to run locally (pathological
memory on sessions.el), so the generated C was patched to match the
source, verified line-for-line against the compiler's own conventions.

MUST be paired with el repo PR #64 (el_strdup_persist for stored engram
fields): per-tick arena reclamation widens the write-corruption window
without it. Verified together: 5h live soak on the recovered production
snapshot, flat RSS, write-field-integrity clean.

Note: dist/soul.c still needs a full elc regen to pick up PR #73's
source changes (consent tiers) — tracked separately; this patch does not
regress that (those changes were never in dist).

awareness.elh

@@ -7,6 +7,7 @@ extern fn elapsed_ms() -> Int
 extern fn elapsed_human() -> String
 extern fn embed_ok() -> Int
 extern fn emit_heartbeat() -> Void
+extern fn auto_term_try_slot(slot_type: String, slot_lbl: String) -> Void
 extern fn proactive_curiosity() -> Bool
 extern fn pulse_count() -> Int
 extern fn pulse_inc() -> Int