v0.8.66: Adopt Moraine as CodeWhale's memory backend (ingestion adapter + MCP recall)

[Hmbown]

Goal

Adopt Moraine (https://github.com/eric-tramel/moraine, Apache-2.0) as CodeWhale's long-term
agent-memory backend: Moraine ingests CodeWhale's persisted sessions losslessly and exposes them as
searchable MCP recall tools (search, search_conversations, list_sessions, get_session,
open). This supersedes the in-repo push/inject memory path (crates/tui/src/memory.rs, which
prepends a <user_memory> block into the system prompt) in favor of pull/recall via Moraine MCP.

Local-first, no prompt injection (MCP is read-only retrieval). CodeWhale keeps persisting sessions;
Moraine indexes them. Supersedes community memory PRs #3381 (@pkeging, memory tags) and
#2933 (@cy2311, hippocampal v2 — glossary/namespaces/rollback/auto-inject) — their ideas inform
the recall layer but the implementation is Moraine-backed, not in-repo.

This is scoped for v0.8.66, not 0.8.65.

Research already done (design is concrete)

Moraine fork: Hmbown/moraine (upstream eric-tramel/moraine, on main @ v0.6.2).

Key finding — the session_json ingest format already fits CodeWhale

crates/moraine-ingest-core/src/dispatch.rs::process_session_json_file reads a whole-file JSON
snapshot and extracts session_doc["messages"] — exactly CodeWhale's shape
(~/.codewhale/sessions/{id}.json → { schema_version, metadata, messages[], artifacts, system_prompt }).
It builds synthetic session_meta + per-session_message records and checkpoints by message index
(incremental ingest), then dispatches each to the harness adapter's normalize().

The fork is already half-wired

crates/moraine-config/src/lib.rs::default_sources() already contains the CodeWhale entry:
harness: "codewhale", glob: "~/.codewhale/sessions/*.json", format: SOURCE_FORMAT_SESSION_JSON.

Work items (Moraine fork)

1. Add adapter crates/moraine-ingest-core/src/sources/codewhale.rs implementing IngestSource
   (harness()="codewhale", format()=SessionJson), mirroring the Hermes session handlers
   (normalize_hermes_session_meta / normalize_hermes_session_message at hermes.rs:791/891).
   Handle CodeWhale content-part types text / thinking / tool_use / tool_result; roles
   user / assistant.
2. Register in sources/mod.rs: pub(crate) mod codewhale; + .register(&codewhale::CODEWHALE)
   in registry(), and add "codewhale" to moraine-config::KNOWN_INGEST_HARNESSES
   (the registry_matches_config_known_harnesses test enforces these agree).
3. Generalize the synthetic builders build_session_meta_record/build_session_message_record
   (dispatch.rs:883/950) to read CodeWhale's nested identity with Hermes-safe fallbacks:
   session_id ← session_doc.session_id OR metadata.id; model ← session_doc.model OR metadata.model;
   session_start ← session_start OR metadata.created_at; last_updated ← last_updated OR metadata.updated_at.
   Hermes files have no metadata, so it's unaffected. compose_hermes_model is a no-op for CodeWhale
   (no base_url).
4. Golden fixture + test mirroring tests/hermes_session_fixture.rs, using a redacted real
   CodeWhale session snapshot.
5. Upstream the adapter to eric-tramel/moraine (PR) so it ships in a Moraine release; keep the
   fork in sync.

Work items (CodeWhale side)

6. Wire moraine-mcp as a recall tool source (stdio moraine mcp server) via CodeWhale's MCP
   config so agents gain the recall tools.
7. Config-gate deprecate the memory.rs push/inject (call sites crates/tui/src/core/engine.rs:801
   and :2996 via crate::memory::compose_block; render prompts.rs:1209; already off by default via
   MemoryConfig.memory_enabled=false) in favor of Moraine pull/recall. Update docs/config comments.

Validation

moraine up ingests ~/.codewhale/sessions; MCP list_sessions/search return CodeWhale sessions
with correct session id / model / timestamps; end-to-end recall in a CodeWhale agent turn.

Known risks / gaps

• CodeWhale session files are whole-file snapshots rewritten on every save; verify the session_json
  "shrank → ignore" guard (dispatch.rs:758) doesn't drop data when a new session has fewer messages
  than a prior one (different file, so likely fine — confirm).
• CodeWhale messages carry no per-message timestamps (only session created_at/updated_at);
  events need synthetic monotonic ts from session start + message index (like hermes_event_dt).
• tool_result content-part exact shape needs confirmation (Anthropic-style
  {type, tool_use_id, content}) — handle defensively.
• Cost/tokens live in metadata.cost / metadata.total_tokens — map into Moraine token accounting if
  desired (non-blocking for recall).

[pkeging]

@Hmbown Thank you for the thorough design. I'm glad the tagging/namespace ideas from #3381 informed the direction — adopting a dedicated memory backend like Moraine makes a lot of sense.
I'd like to help with items 6 and 7 on the CodeWhale side (wiring moraine-mcp as a recall tool source and config-gating the legacy memory.rs path). My experience integrating the WeCom bridge has given me familiarity with CodeWhale's MCP config surface and the relevant code paths.
If you have any early pointers or a rough timeline for v0.8.66, I'll start studying the MCP config and the memory.rs call sites to hit the ground running.
Looking forward to contributing.