docs: Chunk 3 issues 0015-0028 and doc updates

14 issues created covering AGENTS.md refactor prerequisite, skill
implementation workflow grill, bootstrap skills (write-eval, write-skill),
remaining factory skills, and one issue per skill category group through
to chunk closure. All HITL; acceptance criteria for 0017-0028 to be
refined after 0016 grill session.

Doc updates: CONTEXT.md PRD/issue scope clarified (HOW distribution
across architecture-review and issue design notes); ROADMAP.md housekeeping
updated with bootstrap order and issue range; spec/overview.md recent
changes entry added; PRD updated (skills-index: delete → update).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/issues/0019-factory-skills-remaining.md

@@ -0,0 +1,55 @@
+# 0019 — Factory skills: write-adr, write-issue-spec, write-workflow, upgrade-skill, validate-skill
+
+**Type:** HITL  
+**Parent PRD:** `docs/prd/chunk-3-skills-library.md`
+
+## What to build
+
+The remaining 5 factory meta-skills, authored using `write-skill` (0018). `write-adr` must be implemented first within this group — it is called by `design/grill-me` (issue 0020). All skills in this group are new.
+
+Each skill follows the per-skill workflow from issue 0016: upstream review → trigger-first → `write-skill` to author SKILL.md → `write-eval` to produce eval → behavioral test.
+
+**Skills and trigger descriptions** (from skills index):
+
+| Flat name | Trigger description |
+|---|---|
+| `write-adr` | Write an ADR, document this architectural decision, record this decision |
+| `write-issue-spec` | Write a spec for this issue, draft the issue description for X, create a Gitea issue spec |
+| `write-workflow` | Write a workflow for X, chain these skills into a workflow, create a workflow document |
+| `upgrade-skill` | This skill is wrong, fix this skill, update skill X, skill X is behaving incorrectly |
+| `validate-skill` | Check this skill, does this skill meet the standard, review this SKILL.md, audit skill X |
+
+**Key constraints per skill:**
+- `write-adr`: produces `docs/adr/NNN-title.md`; increments ADR number from existing files; never edits an existing Accepted ADR — creates a superseding one instead
+- `write-issue-spec`: produces complete issue body (Why + EARS Requirements with ADDED/MODIFIED/REMOVED delta markers + Design notes + independently completable Task checklist); scale-adaptive; does not post — outputs body for human review; must work for both file-based issues (`docs/issues/`) and Gitea MCP when configured — the active backend is determined at runtime per ADR-0011 (provider-agnostic issue tracker)
+- `write-workflow`: produces `.agents/workflows/<name>.md` with WorkflowContext schema (inputs/outputs per step), HITL gates before every irreversible action, failure paths documented
+- `upgrade-skill`: bumps `version` in frontmatter; always adds a new eval test capturing the correction; never reduces existing eval suite
+- `validate-skill`: severity-rated findings — missing eval = critical; missing failure handling = high; weak trigger description = high
+
+## Implementation notes
+
+Follow the per-skill workflow defined in `docs/notes/skill-implementation-workflow.md` (produced by issue 0016).
+
+**Known upstream sources to review for this category:**
+- `mattpocock/skills` — check for any meta-skill or skill-authoring patterns; record SHAs for any adopted content
+- `bmad-method/bmad-method` — BMAD architect role and ADR-writing patterns; relevant for `write-adr` and `write-issue-spec`
+- `github/spec-kit` and `Fission-AI/OpenSpec` — issue spec and workflow standards; relevant for `write-issue-spec` and `write-workflow`
+- Search agentskills.io and GitHub for open-source validate-skill and upgrade-skill implementations before writing from scratch
+
+For all skills in this group: these are meta-skills with no direct Pocock placeholder equivalent; expect to synthesize from multiple upstreams.
+
+## Acceptance criteria
+
+- [ ] All 5 SKILL.md files exist at `.agents/skills/<skill-name>/SKILL.md`; `metadata.category: factory`; authoring standard met for each
+- [ ] `write-adr` implemented and verified before the design skills issue (0020) begins
+- [ ] Each skill has a co-located eval at `.agents/evals/factory/<skill-name>/eval.yaml` produced via `write-eval`
+- [ ] `install.sh` deploys all 5 to `~/.agents/skills/`
+- [ ] **HITL:** human runs behavioral test per skill; output format matches constraints
+- [ ] **HITL:** human reviews each SKILL.md and eval before committing
+- [ ] _(Further criteria to be refined after issue 0016 grill session)_
+
+## Blocked by
+
+- 0016 (grill defines per-skill workflow)
+- 0017 (`write-eval` needed to produce evals)
+- 0018 (`write-skill` used to author these skills)