chore: gardener housekeeping 2026-03-21

Progressive disclosure split of AGENTS.md (487→152 lines):
- Extracted per-directory AGENTS.md files for all 8 agents + lib/
- Root AGENTS.md now serves as a table of contents with summary table
- All watermarks updated to 16e430e

Grooming results:
- Promoted #469 (WATCH flow missing curl) and #436 (idle_pane_count bug) to backlog
- 12 dust items classified, no groups ripe for bundling yet
- No blocked issues, no AD violations

planner/AGENTS.md

@@ -0,0 +1,43 @@
+<!-- last-reviewed: 16e430ebce905cf722f91ae1f873faea1c64d890 -->
+# Planner Agent
+
+**Role**: Strategic planning, executed directly from cron via tmux + Claude.
+Phase 0 (preflight): pull latest code, load persistent memory from
+`planner/MEMORY.md`. Phase 1 (prediction-triage): triage
+`prediction/unreviewed` issues filed by the Predictor — for each prediction:
+promote to action, promote to backlog, watch (relabel to prediction/backlog),
+or dismiss with reasoning. Promoted predictions compete with vision gaps for
+the per-cycle issue limit. Phase 2 (strategic-planning): resource+leverage gap
+analysis — reasons about VISION.md, RESOURCES.md, formula catalog, and project
+state to create up to 5 total issues (including promotions) prioritized by
+leverage. Phase 3 (journal-and-memory): write daily journal entry (committed to
+git) and update `planner/MEMORY.md` (committed to git). Phase 4 (commit-and-pr):
+one commit with all file changes, push, create PR. AGENTS.md maintenance is
+handled by the Gardener.
+
+**Trigger**: `planner-run.sh` runs weekly via cron. It creates a tmux session
+with `claude --model opus`, injects `formulas/run-planner.toml` as context,
+monitors the phase file, and cleans up on completion or timeout. No action
+issues — the planner is a nervous system component, not work.
+
+**Key files**:
+- `planner/planner-run.sh` — Cron wrapper + orchestrator: lock, memory guard,
+  sources disinto project config, creates tmux session, injects formula prompt,
+  monitors phase file, handles crash recovery, cleans up
+- `formulas/run-planner.toml` — Execution spec: five steps (preflight,
+  prediction-triage, strategic-planning, journal-and-memory, commit-and-pr)
+  with `needs` dependencies. Claude executes all steps in a single interactive
+  session with tool access
+- `planner/MEMORY.md` — Persistent memory across runs (committed to git)
+- `planner/journal/*.md` — Daily raw logs from each planner run (committed to git)
+
+**Future direction**: The Predictor files prediction issues daily for the planner
+to triage. The next step is evidence-gated deployment (see
+`docs/EVIDENCE-ARCHITECTURE.md`): replacing human "ship it" decisions with
+automated gates across dimensions (holdout, red-team, user-test, evolution
+fitness, protocol metrics, funnel). Not yet implemented.
+
+**Environment variables consumed**:
+- `CODEBERG_TOKEN`, `CODEBERG_REPO`, `CODEBERG_API`, `PROJECT_NAME`, `PROJECT_REPO_ROOT`
+- `PRIMARY_BRANCH`, `CLAUDE_MODEL` (set to opus by planner-run.sh)
+- `MATRIX_TOKEN`, `MATRIX_ROOM_ID`, `MATRIX_HOMESERVER`