The state machine's `Stage` enum becomes the source of truth for pipeline
state. Six stages of work land together:
1. Clean wire vocabulary (`coding`, `merge`, `merge_failure`, ...) replaces
legacy directory-style strings (`2_current`, `4_merge`, ...) on the wire.
`Stage::from_dir` accepted both during deployment; new writes always
emit the clean form via `stage_dir_name`. Lexicographic `dir >= "5_done"`
checks in lifecycle.rs become typed `matches!` checks since the new
vocabulary doesn't sort in pipeline order.
2. `crdt_state::write_item` takes typed `&Stage`, serialising via
`stage_dir_name` at the CRDT boundary. `#[cfg(test)] write_item_str`
parses legacy strings for test fixtures.
3. `WorkItem::stage()` returns typed `crdt_state::Stage`; `stage_str()`
is gone from the public API. Projection dispatches on the typed enum.
4. `frozen` becomes an orthogonal CRDT register. `Stage::Frozen` and
`PipelineEvent::Freeze`/`Unfreeze` are removed; `transition_to_frozen`/
`unfrozen` set the flag directly without touching the stage register.
5. Watcher sweep and `tool_update_story`'s `blocked` setter route through
`apply_transition` so the typed transition table validates every
stage change. `update_story` gains a `frozen` field for symmetry.
6. One-shot startup migration rewrites pre-934 directory-style stage
registers (and sets `frozen=true` on items previously at `7_frozen`).
`Stage::from_dir` drops legacy aliases. The db boundary keeps a small
normaliser so callers with legacy strings (MCP, tests) still work.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
After 932 (review_hold register) and 933 (item_type + epic registers), the
remaining production yaml_legacy callers all had typed CRDT equivalents.
Migrated:
- agents/lifecycle.rs:
- transition_to_merge_failure writes to MergeJob.error CRDT entry instead
of YAML body. The legacy `merge_failure: "..."` front-matter write is gone.
- reject_story_from_qa inlines the QA-rejection notes append; no longer
needs yaml_legacy::write_rejection_notes_to_content.
- fields_to_clear_transform helper deleted along with all five callers —
blocked/retry_count/merge_failure are typed CRDT fields now, so clearing
the equivalent YAML keys is redundant.
- http/workflow/pipeline.rs:
- load_pipeline_state reads merge_failure from MergeJob.error (mirrors
status_tools.rs).
- validate_story_dirs checks the typed CRDT `name` register instead of
parsing YAML front matter.
- http/mcp/status_tools.rs: review_hold reads the typed CRDT register
(yaml_residue wrap was the last one in this file).
- http/mcp/story_tools/criteria.rs: story_name reads from CRDT.
- service/agents/mod.rs::get_work_item_content: name/agent come from CRDT.
- service/notifications/io/mod.rs::read_story_name: same.
- http/workflow/bug_ops/{bug,refactor}.rs: name-fallback paths drop YAML
parsing in favour of the CRDT-derived item.name.
Dead helpers removed from db/yaml_legacy.rs:
yaml_residue, write_merge_failure_in_content, write_rejection_notes_to_content,
clear_front_matter_field_in_content, write_review_hold_in_content,
clear_front_matter_field, write_review_hold (the last four shipped in 932).
Remaining surface: FrontMatter / StoryMetadata structs, parse_front_matter,
set_front_matter_field — kept for `coverage_baseline` writes via
test_results.rs and the generic update_story front_matter escape hatch.
Test fixtures rewritten to seed the CRDT register instead of relying on
YAML parsing during write_item_with_content:
- has_review_hold_returns_* tests
- item_type_from_id_uses_crdt_register_for_numeric_ids
- tool_list_epics_shows_member_rollup
- get_work_item_content (both copies — http/agents + service/agents)
- validate_story_dirs_missing_name_in_crdt
- server_side_merge_*_sets_merge_failure (assert MergeJob.error, not YAML)
cargo fmt --check, clippy --all-targets -- -D warnings, and the
2856-test suite all pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>