docs: list implement in the README's engineering user-invoked skills

implement is the central Main Flow step but was missing from the
public Reference list. Add it after to-tickets.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.changeset/to-issues-wide-refactor.md

@@ -0,0 +1,5 @@
+---
+"mattpocock-skills": minor
+---
+
+Split the **`to-issues`** skill into a lean **Process** and a **Reference** section, and teach it to handle a **wide refactor** — a single mechanical change (like renaming a column) whose **blast radius** fans across the whole codebase, breaking thousands of call sites at once so no vertical slice can land green. The drafting step now points at two co-located reference blocks: the **Vertical slice rules** for ordinary tracer bullets, and **Wide refactors**, which slices the change by **expand–contract** (expand the new form beside the old, migrate call sites in batches sized by blast radius, then contract the old form away) so CI stays green batch to batch — or, when it can't, only at a final integrate-and-verify issue. The issue body template moves into Reference too.

.changeset/wayfinder-tracker-indirection.md

@@ -0,0 +1,7 @@
+---
+"mattpocock-skills": patch
+---
+
+Fix **`wayfinder`** hardcoding the issue-tracker doc path, which broke the indirection the rest of the suite relies on.
+
+`to-issues`, `to-prd`, and `triage` never name a path — they resolve the tracker through the `### Issue tracker` block that `setup-matt-pocock-skills` writes into `CLAUDE.md` / `AGENTS.md`, which points at the tracker doc wherever it lives. Wayfinder instead pinned the literal `docs/agents/issue-tracker.md`, so in a repo that keeps its agent docs elsewhere it silently fell back to the local-markdown tracker — even one whose `CLAUDE.md` clearly declares GitHub issues. It now resolves the doc via that same pointer and reads its "Wayfinding operations" section by name, keeping the indirection consistent across the suite.

README.md

@@ -156,6 +156,7 @@ Skills I use daily for code work.
 - **[setup-matt-pocock-skills](./skills/engineering/setup-matt-pocock-skills/SKILL.md)** — Configure this repo for the engineering skills (issue tracker, triage labels, domain doc layout). Run once per repo before using the other engineering skills.
 - **[to-spec](./skills/engineering/to-spec/SKILL.md)** — Turn the current conversation into a spec and publish it to the issue tracker. No interview — just synthesizes what you've already discussed.
 - **[to-tickets](./skills/engineering/to-tickets/SKILL.md)** — Break any plan, spec, or conversation into a set of tracer-bullet tickets, each declaring its blocking edges — written as text in a local file, or as native blocking links on a real tracker.
+- **[implement](./skills/engineering/implement/SKILL.md)** — Build the work described by a spec or set of tickets, driving `/tdd` at pre-agreed seams and closing out with `/code-review` before committing.
 - **[wayfinder](./skills/engineering/wayfinder/SKILL.md)** — Plan a huge chunk of work, more than one agent session can hold, as a shared map of investigation tickets on the issue tracker — resolve them one at a time until the way to the destination is clear.
 
 **Model-invoked**

docs/engineering/to-tickets.md

@@ -41,6 +41,10 @@ The whole skill turns on one distinction. A **horizontal** slice ships one layer
 
 Before slicing, `to-tickets` looks for prefactoring — "make the change easy, then make the easy change" — and orders that work first. It then quizzes you on the breakdown (granularity, blocking edges, what to merge or split) before publishing anything, and publishes blockers first so each ticket's "Blocked by" can reference a real ticket.
 
+## The wide-refactor exception
+
+One shape breaks the tracer-bullet rule: a **wide refactor** — a single mechanical change (rename a column, retype a shared symbol) whose **blast radius** fans across the whole codebase, so one edit breaks thousands of call sites at once and no vertical slice can land green. `to-tickets` slices it as **expand–contract** instead: expand (add the new form beside the old so nothing breaks), migrate (move call sites over in batches sized by blast radius, one ticket per batch, CI green throughout because the old form still exists), then contract (delete the old form once no caller remains). When even the batches can't stay green alone, they share an integration branch that all block a final integrate-and-verify ticket, and green is promised only there.
+
 ## Where it fits
 
 `to-tickets` is a step in the main build chain:

skills/engineering/to-tickets/SKILL.md

@@ -37,6 +37,8 @@ Break the work into **tracer bullet** tickets.
 
 Give each ticket its **blocking edges** — the other tickets that must complete before it can start. A ticket with no blockers can start immediately.
 
+**Wide refactors are the exception to vertical slicing.** A **wide refactor** is one mechanical change — rename a column, retype a shared symbol — whose **blast radius** fans across the whole codebase, so a single edit breaks thousands of call sites at once and no vertical slice can land green. Don't force it into a tracer bullet; sequence it as **expand–contract**. First expand: add the new form beside the old so nothing breaks. Then migrate the call sites over in batches sized by blast radius (per package, per directory), each batch its own ticket blocked by the expand, keeping CI green batch to batch because the old form still exists. Finally contract: delete the old form once no caller remains, in a ticket blocked by every migrate batch. When even the batches can't stay green alone, keep the sequence but let them share an integration branch that all block a final integrate-and-verify ticket — green is promised only there.
+
 ### 4. Quiz the user
 
 Present the proposed breakdown as a numbered list. For each ticket, show:

skills/engineering/wayfinder/SKILL.md

@@ -22,7 +22,7 @@ The map is a single issue on this repo's issue tracker, labelled `wayfinder:map`
 
 The map is an **index**, not a store. It lists the decisions made and points at the tickets that hold their detail; a decision lives in exactly one place — its ticket — so the map never restates it, only gists it and links.
 
-**Where the map, its child tickets, blocking, and frontier queries physically live is tracker-specific.** Consult `docs/agents/issue-tracker.md` (the "Wayfinding operations" section) for how _this_ repo expresses them. If that doc is absent, default to the local-markdown tracker.
+**Where the map, its child tickets, blocking, and frontier queries physically live is tracker-specific.** The issue tracker should have been provided to you — run `/setup-matt-pocock-skills` if not. Consult the tracker doc's "Wayfinding operations" section for how _this_ repo expresses them. If no tracker has been provided, default to the local-markdown tracker.
 
 ### The map body