fix(compression): route-aware pruned estimate at remaining pressure sibling sites

Follow-up to the mid-turn pre-API guard fix (#96995 / #97602): sweep the
remaining call sites that derive automatic compression pressure from a
generic estimate over the assembled durable history, which on a compacted
native-Codex session overstates the wire payload by orders of magnitude.

- agent/turn_context.py idle-triggered compaction: use
  _preflight_request_tokens (anchor -> native pruned -> generic) instead
  of the raw generic request estimate, so resuming a compacted codex
  session after an idle gap does not fire a compaction the next request
  never needed.
- agent/turn_context.py uncompressed-session overflow-warn RE-ARM: match
  the warn site's route-aware figure so the dedup re-arms correctly on
  native sessions.
- agent/conversation_loop.py post-response should_compress fallback
  (last_prompt_tokens==0, i.e. no provider usage after a disconnect or
  gateway restart — the unanchored case in #97602's repro): route through
  _midturn_request_pressure_tokens instead of the generic figure.

Left alone deliberately: provider-proven overflow recovery paths (413 /
context-length errors — the provider already proved the request does not
fit, figures there only arm recovery and score progress), compression
progress before/after pairs (relative deltas on the same scale), manual
/compress display estimates (gateway/CLI/ACP feedback, not automatic
triggers), MoA advisor budget trimming (not a codex-native wire payload),
and context_compressor internals (measure local durable-history shrink).

agent/conversation_loop.py

@@ -7660,8 +7660,18 @@ def run_conversation(
                     # these add 20-30K tokens the messages-only
                     # estimate misses, which can skip compression
                     # past the configured threshold (#14695).
-                    _real_tokens = estimate_request_tokens_rough(
-                        messages, tools=agent.tools or None
+                    # Route-aware (#96995/#97602 class): on a compacted
+                    # native-Codex session the generic durable-history
+                    # figure overstates the wire and would false-trigger
+                    # compression here exactly like the pre-API guard —
+                    # this fallback runs precisely when no provider usage
+                    # is available (post-disconnect / gateway restart),
+                    # the unanchored case from #97602's repro.
+                    _real_tokens = _midturn_request_pressure_tokens(
+                        agent,
+                        messages,
+                        active_system_prompt or "",
+                        estimate_messages_tokens_rough(messages),
                     )
 
                 if (

agent/turn_context.py

@@ -883,10 +883,15 @@ def build_turn_context(
         _idle_gap = time.time() - getattr(agent, "_last_activity_ts", time.time())
         if _idle_gap >= _idle_after:
             _compressor = agent.context_compressor
-            _idle_tokens = estimate_request_tokens_rough(
+            # Route-aware pressure (#96995/#97602 class): on a compacted
+            # native-Codex session the generic durable-history figure
+            # overstates the wire by orders of magnitude and would fire an
+            # idle compaction the next request never needed. Reuse the
+            # preflight estimator (anchor → native pruned → generic).
+            _idle_tokens = _preflight_request_tokens(
+                agent,
                 messages,
-                system_prompt=active_system_prompt or "",
-                tools=agent.tools or None,
+                active_system_prompt or "",
             )
             # Post-compression target size: don't summarise a thread already
             # below what compaction would reduce it to.
@@ -1297,10 +1302,16 @@ def build_turn_context(
                 if callable(_clear_warn):
                     _clear_warn()
             else:
-                _uncompressed_tokens = estimate_request_tokens_rough(
+                # Route-aware (#96995/#97602 class): the warn site in the
+                # conversation loop now measures the checkpoint-pruned wire
+                # payload on native-Codex sessions, so the re-arm must use
+                # the same figure — otherwise a compacted session that fits
+                # on the wire never clears the dedup and future genuine
+                # overflow warnings stay suppressed.
+                _uncompressed_tokens = _preflight_request_tokens(
+                    agent,
                     messages,
-                    system_prompt=active_system_prompt or "",
-                    tools=agent.tools or None,
+                    active_system_prompt or "",
                 )
                 if _uncompressed_tokens <= _ctx_len:
                     _clear_warn = getattr(