docs(project): add m4-5 workspace RFI baseline and benchmark harness

docs/SUMMARY.md

@@ -2,7 +2,7 @@
 
 This file is the canonical table of contents for the documentation system.
 
-Last refreshed: **February 25, 2026**.
+Last refreshed: **February 28, 2026**.
 
 ## Language Entry
 
@@ -110,5 +110,6 @@ Last refreshed: **February 25, 2026**.
 - [project/README.md](project/README.md)
 - [project-triage-snapshot-2026-02-18.md](project-triage-snapshot-2026-02-18.md)
 - [docs-audit-2026-02-24.md](docs-audit-2026-02-24.md)
+- [project/m4-5-rfi-spike-2026-02-28.md](project/m4-5-rfi-spike-2026-02-28.md)
 - [i18n-gap-backlog.md](i18n-gap-backlog.md)
 - [docs-inventory.md](docs-inventory.md)

docs/docs-inventory.md

@@ -2,7 +2,7 @@
 
 This inventory classifies documentation by intent and canonical location.
 
-Last reviewed: **February 24, 2026**.
+Last reviewed: **February 28, 2026**.
 
 ## Classification Legend
 
@@ -124,6 +124,7 @@ These are valuable context, but **not strict runtime contracts**.
 |---|---|
 | `docs/project-triage-snapshot-2026-02-18.md` | Snapshot |
 | `docs/docs-audit-2026-02-24.md` | Snapshot (docs architecture audit) |
+| `docs/project/m4-5-rfi-spike-2026-02-28.md` | Snapshot (M4-5 workspace split RFI baseline and execution plan) |
 | `docs/i18n-gap-backlog.md` | Snapshot (i18n depth gap tracking) |
 
 ## Maintenance Contract

docs/project/README.md

@@ -6,6 +6,7 @@ Time-bound project status snapshots for planning documentation and operations wo
 
 - [../project-triage-snapshot-2026-02-18.md](../project-triage-snapshot-2026-02-18.md)
 - [../docs-audit-2026-02-24.md](../docs-audit-2026-02-24.md)
+- [m4-5-rfi-spike-2026-02-28.md](m4-5-rfi-spike-2026-02-28.md)
 
 ## Scope
 

docs/project/m4-5-rfi-spike-2026-02-28.md

@@ -0,0 +1,151 @@
+# M4-5 Multi-Crate Workspace RFI Spike (2026-02-28)
+
+Status: RFI complete, extraction execution pending.
+Issue: https://github.com/zeroclaw-labs/zeroclaw/issues/2263
+Linear parent: RMN-243
+
+## Scope
+
+This spike is strictly no-behavior-change planning for the M4-5 workspace split.
+
+Goals:
+- capture reproducible compile baseline metrics
+- define crate boundary and dependency contract
+- define CI/feature-matrix impact and rollback posture
+- define stacked PR slicing plan (XS/S/M)
+
+Out of scope:
+- broad API redesign
+- feature additions bundled with structure work
+- one-shot mega-PR extraction
+
+## Baseline Compile Metrics
+
+### Repro command
+
+```bash
+scripts/ci/m4_5_rfi_baseline.sh /tmp/zeroclaw-m4rfi-target
+```
+
+### Preflight compile blockers observed on `origin/main`
+
+Before timing could run cleanly, two compile blockers were found:
+
+- `src/gateway/mod.rs:2176`: `run_gateway_chat_with_tools` call missing `session_id` argument
+- `src/providers/cursor.rs:233`: `ChatResponse` initializer missing `quota_metadata`
+
+RFI includes minimal compile-compat fixes for these two blockers so measurements are reproducible.
+
+### Measured results (Apple Silicon macOS, local workspace)
+
+| Phase | real(s) | status |
+|---|---:|---|
+| A: cold `cargo check --workspace --locked` | 306.47 | pass |
+| B: cold-ish `cargo build --workspace --locked` | 219.07 | pass |
+| C: warm `cargo check --workspace --locked` | 0.84 | pass |
+| D: incremental `cargo check` after touching `src/main.rs` | 6.19 | pass |
+
+Observations:
+- cold check is the dominant iteration tax
+- warm-check performance is excellent once target artifacts exist
+- incremental behavior is acceptable but sensitive to wide root-crate coupling
+
+## Current Workspace Snapshot
+
+Current workspace members:
+- `.` (`zeroclaw` monolith crate)
+- `crates/robot-kit`
+
+Code concentration still sits in the monolith. Large hotspots include:
+- `src/config/schema.rs`
+- `src/channels/mod.rs`
+- `src/onboard/wizard.rs`
+- `src/agent/loop_.rs`
+- `src/gateway/mod.rs`
+
+## Proposed Boundary Contract
+
+Target crate topology for staged extraction:
+
+1. `crates/zeroclaw-types`
+- shared DTOs, enums, IDs, lightweight cross-domain traits
+- no provider/channel/network dependencies
+
+2. `crates/zeroclaw-core`
+- config structs + validation, provider trait contracts, routing primitives, policy helpers
+- depends on `zeroclaw-types`
+
+3. `crates/zeroclaw-memory`
+- memory traits/backends + hygiene/snapshot plumbing
+- depends on `zeroclaw-types`, `zeroclaw-core` contracts only where required
+
+4. `crates/zeroclaw-channels`
+- channel adapters + inbound normalization
+- depends on `zeroclaw-types`, `zeroclaw-core`, `zeroclaw-memory`
+
+5. `crates/zeroclaw-api`
+- gateway/webhook/http orchestration
+- depends on `zeroclaw-types`, `zeroclaw-core`, `zeroclaw-memory`, `zeroclaw-channels`
+
+6. `crates/zeroclaw-bin` (or keep root binary package name stable)
+- CLI entrypoints + wiring only
+
+Dependency rules:
+- no downward imports from foundational crates into higher layers
+- channels must not depend on gateway/http crate
+- keep provider-specific SDK deps out of `zeroclaw-types`
+- maintain feature-flag parity at workspace root during migration
+
+## CI / Feature-Matrix Impact
+
+Required CI adjustments during migration:
+- add workspace compile lane (`cargo check --workspace --locked`)
+- add package-focused lanes for extracted crates (`-p zeroclaw-types`, `-p zeroclaw-core`, etc.)
+- keep existing runtime behavior lanes (`test`, `sec-audit`, `codeql`) unchanged until final convergence
+- update path filters so crate-local changes trigger only relevant crate tests plus contract smoke tests
+
+Guardrails:
+- changed-line strict-delta lint remains mandatory
+- each extraction PR must include no-behavior-change assertion in PR body
+- each step must include explicit rollback note
+
+## Rollback Strategy
+
+Per-step rollback (stack-safe):
+1. revert latest extraction PR only
+2. re-run workspace compile + existing CI matrix
+3. keep binary entrypoint and config contract untouched until final extraction stage
+
+Abort criteria:
+- unexpected runtime behavior drift
+- CI lane expansion causes recurring queue stalls without signal gain
+- feature-flag compatibility regressions
+
+## Stacked PR Slicing Plan
+
+### PR-1 (XS)
+- add crate shells + workspace wiring (`types/core`), no symbol moves
+- objective: establish scaffolding and CI package lanes
+
+### PR-2 (S)
+- extract low-churn shared types into `zeroclaw-types`
+- add re-export shim layer to preserve existing import paths
+
+### PR-3 (S)
+- extract config/provider contracts into `zeroclaw-core`
+- keep runtime call sites unchanged via compatibility re-exports
+
+### PR-4 (M)
+- extract memory subsystem crate and move wiring boundaries
+- run full memory + gateway regression suite
+
+### PR-5 (M)
+- extract channels/api orchestration seams
+- finalize package ownership and remove temporary re-export shims
+
+## Next Execution Step
+
+Open first no-behavior-change extraction PR from this RFI baseline:
+- scope: workspace crate scaffolding + CI package lanes only
+- no runtime behavior changes
+- explicit rollback command included in PR body

scripts/ci/m4_5_rfi_baseline.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "${1:-}" == "-h" || "${1:-}" == "--help" ]]; then
+  cat <<'USAGE'
+Usage: scripts/ci/m4_5_rfi_baseline.sh [target_dir]
+
+Run reproducible compile-timing probes for the current workspace.
+The script prints a markdown table with real-time seconds and pass/fail status
+for each benchmark phase.
+USAGE
+  exit 0
+fi
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+TARGET_DIR="${1:-${ROOT_DIR}/target-rfi}"
+
+cd "${ROOT_DIR}"
+
+if [[ ! -f Cargo.toml ]]; then
+  echo "error: Cargo.toml not found at ${ROOT_DIR}" >&2
+  exit 1
+fi
+
+run_timed() {
+  local label="$1"
+  shift
+
+  local timing_file
+  timing_file="$(mktemp)"
+  local status="pass"
+
+  if /usr/bin/time -p "$@" >/dev/null 2>"${timing_file}"; then
+    status="pass"
+  else
+    status="fail"
+  fi
+
+  local real_time
+  real_time="$(awk '/^real / { print $2 }' "${timing_file}")"
+  rm -f "${timing_file}"
+
+  if [[ -z "${real_time}" ]]; then
+    real_time="n/a"
+  fi
+
+  printf '| %s | %s | %s |\n' "${label}" "${real_time}" "${status}"
+
+  [[ "${status}" == "pass" ]]
+}
+
+printf '# M4-5 RFI Baseline\n\n'
+printf '- Timestamp (UTC): %s\n' "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
+printf '- Commit: `%s`\n' "$(git rev-parse --short HEAD)"
+printf '- Target dir: `%s`\n\n' "${TARGET_DIR}"
+printf '| Phase | real(s) | status |\n'
+printf '|---|---:|---|\n'
+
+rm -rf "${TARGET_DIR}"
+
+set +e
+run_timed "A: cold cargo check" env CARGO_TARGET_DIR="${TARGET_DIR}" cargo check --workspace --locked
+run_timed "B: cold-ish cargo build" env CARGO_TARGET_DIR="${TARGET_DIR}" cargo build --workspace --locked
+run_timed "C: warm cargo check" env CARGO_TARGET_DIR="${TARGET_DIR}" cargo check --workspace --locked
+touch src/main.rs
+run_timed "D: incremental cargo check after touch src/main.rs" env CARGO_TARGET_DIR="${TARGET_DIR}" cargo check --workspace --locked
+set -e