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.el

@@ -527,9 +527,27 @@ fn awareness_run() -> Void {
     let scan_ms: Int = beat_ms / 2
 
     while true {
+        // Arena-scope each tick: awareness_run() is a background loop, not an
+        // HTTP request, so nothing ever called el_request_start/el_request_end
+        // for this thread. Per the runtime's own convention (el_runtime.c),
+        // any thread that never enters a request/arena scope is treated as a
+        // one-shot CLI program whose allocations are intentionally permanent —
+        // so every el_strdup/el_strbuf/jb_finish string built during perceive(),
+        // emit_heartbeat(), and proactive_curiosity() (JSON payloads, search
+        // results, string concatenation via +) leaked forever, once per tick.
+        // el_arena_push()/el_arena_pop() are the same builtins the EL compiler
+        // itself uses to scope allocations per function/statement (see
+        // codegen.el's fn_arena_mark / stmt_mark usage) — mirroring that here
+        // reclaims everything allocated in one tick as soon as the tick ends.
+        // Safe: state_set/state_get persist through a separate global table
+        // (el_strdup_persist, outside the arena) — state_get's return value is
+        // only an arena-tracked *copy* of the persisted value, scoped to this
+        // tick's use, which is exactly what should be reclaimed here.
+        let tick_mark: Any = el_arena_push()
         let running: String = state_get("soul.running")
         if str_eq(running, "false") {
             println("[awareness] exiting")
+            el_arena_pop(tick_mark)
             return ""
         }
         let did_work: Bool = one_cycle()
@@ -593,6 +611,7 @@ fn awareness_run() -> Void {
         }
 
         sleep_ms(tick_ms)
+        el_arena_pop(tick_mark)
     }
 }