refactor(dream): replace two-phase Dream class with simple cron + process_direct (#3990)

* refactor(dream): replace two-phase Dream class with simple cron + process_direct

- Remove the heavyweight Dream class (AgentRunner-based two-phase system)
  from nanobot/agent/memory.py
- Delete dream_phase1.md and dream_phase2.md templates
- New dream.md template serves as the consolidation prompt
- Cron callback uses agent.process_direct(prompt, session_key=\"dream\")
  instead of agent.dream.run()
- Always performs git auto_commit after execution
- /dream command updated to use process_direct + git commit
- DreamConfig kept for backward compatibility; deprecated fields
  (model_override, max_batch_size, max_iterations, annotate_line_ages)
  are ignored but accepted in config
- interval_h remains configurable via agents.defaults.dream.interval_h
- Update tests and webui settings to match new architecture

* feat(loop): add ephemeral mode to process_direct, skip history writes for Dream

When ephemeral=True, _state_save skips enforce_file_cap (which calls
raw_archive -> append_history) and consolidator.maybe_consolidate_by_tokens.
This prevents Dream sessions from creating a positive feedback loop where
they process their own output. The session IS still saved to disk.

* fix(loop): skip extra hooks for ephemeral sessions (Dream)

* feat(dream): per-run timestamped sessions with rotation for WebUI

* test(config): restore DreamConfig schedule and alias tests

* fix(dream): include LLM response summary in git auto-commit message

The old two-phase Dream class included the Phase 1 analysis in the git
commit message body. The new single-phase version lost this. Restore it
by extracting resp.content from the process_direct return value and
appending it to the commit message in both the cron handler and the
/dream command.

* fix(test): accept ephemeral kwarg in test_openai_api fake_process

* refactor(dream): merge dream_session.py into MemoryStore

The standalone dream_session.py module only contained three small helpers
that all revolve around MemoryStore concerns (session keys, commit messages,
file pruning). Fold them into MemoryStore as @staticmethod to reduce
indirection and avoid a 35-line module with no independent reason to exist.

* fix(test): address code review — patch correct instance, use actual function

- Fix test_ephemeral_skips_raw_archive to patch loop.context.memory
  instead of the fixture's separate MemoryStore instance
- Fix TestDreamCommitMessage to call MemoryStore.build_dream_commit_message
  instead of reimplementing the logic inline
- Move Dream helpers in memory.py above the Consolidator section comment
  to avoid misleading visual boundary

* fix(dream): gate cursor advancement and restrict tools

maintainer edit: Dream now processes backlog from the oldest unprocessed entries, only advances the cursor after a completed ephemeral run, and uses a restricted file-only tool registry for background consolidation.

* fix(dream): skip idle compact for dream sessions

Dream runs use internal dream:* sessions that are pruned by Dream retention. Exclude them from AutoCompact scheduling, archive execution, and summary injection so idle-session compaction cannot truncate Dream transcripts.

* fix(dream): keep batched history isolated

* feat(dream): tag archived memory for single-phase Dream

---------

Co-authored-by: Xubin Ren <52506698+Re-bin@users.noreply.github.com>

nanobot/command/builtin.py

@@ -305,17 +305,52 @@ async def cmd_dream(ctx: CommandContext) -> OutboundMessage:
     msg = ctx.msg
 
     async def _run_dream():
+        from nanobot.agent.memory import MemoryStore
+
+        dream_session_key = MemoryStore.dream_session_key
+        build_dream_commit_message = MemoryStore.build_dream_commit_message
+        prune_dream_sessions = MemoryStore.prune_dream_sessions
+
+        store = loop.context.memory
+        content = ""
+        resp = None
         t0 = time.monotonic()
         try:
-            did_work = await loop.dream.run()
+            result = store.build_dream_prompt()
+            if result is None:
+                await loop.bus.publish_outbound(OutboundMessage(
+                    channel=msg.channel, chat_id=msg.chat_id,
+                    content="Dream: nothing to process.",
+                ))
+                return
+            prompt, last_cursor = result
+            key = dream_session_key()
+            resp = await loop.process_direct(
+                prompt,
+                session_key=key,
+                ephemeral=True,
+                tools=store.build_dream_tools(),
+            )
             elapsed = time.monotonic() - t0
-            if did_work:
+            if MemoryStore.dream_run_completed(resp):
+                store.set_last_dream_cursor(last_cursor)
                 content = f"Dream completed in {elapsed:.1f}s."
             else:
-                content = "Dream: nothing to process."
+                content = (
+                    f"Dream did not complete after {elapsed:.1f}s; "
+                    "memory cursor was not advanced."
+                )
         except Exception as e:
             elapsed = time.monotonic() - t0
             content = f"Dream failed after {elapsed:.1f}s: {e}"
+        finally:
+            if store.git.is_initialized():
+                commit_msg = build_dream_commit_message("dream: manual run", resp)
+                sha = store.git.auto_commit(commit_msg)
+                if sha:
+                    content += f" (commit {sha})"
+            store.compact_history()
+            prune_dream_sessions(loop.sessions.sessions_dir)
         await loop.bus.publish_outbound(OutboundMessage(
             channel=msg.channel, chat_id=msg.chat_id, content=content,
         ))