ML-196: add application-task pi prompt template

Introduces /application-task for working on Backlog.md tasks end-to-end:
- Pre-flight: read docs, load task plan, load relevant skills
- Execution: present plan, short loops, log progress, handle scope
- Done vs Complete: finalize without archiving, per Backlog.md workflow

backlog/tasks/ml-196 - Add-pi-template-to-work-on-application-task.md

@@ -1,9 +1,10 @@
 ---
 id: ML-196
 title: Add pi template to work on application task
-status: To Do
+status: Done
 assignee: []
 created_date: "2026-05-22 09:40"
+updated_date: "2026-05-22 14:12"
 labels: []
 dependencies: []
 ordinal: 33000
@@ -17,3 +18,48 @@ ordinal: 33000
 - Solicit loading relevant skills
 - Make sure it'd done, and not complete
 <!-- SECTION:DESCRIPTION:END -->
+
+## Acceptance Criteria
+
+<!-- AC:BEGIN -->
+
+- [x] #1 Template file exists at .pi/prompts/application-task.md with correct frontmatter (description + argument-hint)
+- [x] #2 Template instructs agent to read docs/architecture.md and docs/project-conventions.md before writing code without summarizing their contents
+- [x] #3 Template instructs agent to load relevant skills based on their descriptions and triggers, without hardcoding a domain→skill mapping
+- [x] #4 Template distinguishes Done status from task_complete/task_archive per Backlog.md finalization workflow
+- [x] #5 Template covers the full Backlog.md execution workflow: pre-flight → present plan → work loops → finalization → after finalization
+<!-- AC:END -->
+
+## Implementation Plan
+
+<!-- SECTION:PLAN:BEGIN -->
+
+Create `.pi/prompts/application-task.md` that:
+
+1. **Solicits architecture reading** — instructs the agent to read `docs/architecture.md` and `docs/project-conventions.md` before touching code
+2. **Solicits loading relevant skills** — maps task domains (database, UI, testing, workers, APIs, etc.) to their corresponding `.agents/skills/*/SKILL.md` files and instructs the agent to load all relevant ones
+3. **Distinguishes done from complete** — follows the Backlog.md Task Finalization workflow: verify AC, verify DoD, run tests, write Final Summary, set status to "Done". Explicitly warns against calling `task_complete` or `task_archive` for marking work finished.
+4. **Follows Backlog.md execution workflow** — mark In Progress, present plan, work in short loops, log progress, handle scope changes, finalize properly
+
+The template uses `argument-hint: "<TASK-ID>"` for autocomplete compatibility with the `/application-task <ID>` invocation pattern.
+
+Updated pre-flight after review: point 1 no longer summarizes doc contents, point 3 no longer hardcodes a domain→skill mapping — instead instructs agent to load skills based on their own descriptions and triggers.
+
+<!-- SECTION:PLAN:END -->
+
+## Final Summary
+
+<!-- SECTION:FINAL_SUMMARY:BEGIN -->
+
+Created `.pi/prompts/application-task.md` — a pi prompt template for working on Backlog.md tasks end-to-end.
+
+**What it does:**
+
+- **Pre-flight phase**: instructs the agent to read `docs/architecture.md` and `docs/project-conventions.md` before writing code, load the task plan from Backlog.md, and identify + read all relevant `.agents/skills/` files based on the task's domain (database, UI, testing, workers, APIs, etc.)
+- **Execution phase**: follows the Backlog.md Task Execution workflow — mark In Progress, present plan for approval, work in short loops, log progress, handle scope changes
+- **Done vs Complete distinction**: explicitly warns against `task_complete`/`task_archive` and follows the Backlog.md Task Finalization workflow (verify AC, verify DoD, run tests, write Final Summary, set status to "Done")
+- **After finalization**: reminders about not autonomously creating tasks and proper subtask handoff
+
+**Template**: invocable as `/application-task <TASK-ID>` via pi's prompt template system.
+
+<!-- SECTION:FINAL_SUMMARY:END -->