Add Pretty Table project: plan, accepted documents and code

Business Case, Stakeholder Analysis, Project Plan and milestone MIL-001
with review records RC-001 to RC-003, then the Python project: PrettyTable
Pokemon table, constants, pytest tests, pyproject.toml, Doxyfile, CI
workflow and README.

Task: MIL-001#1
Task: MIL-001#2
Task: MIL-001#3
Task: MIL-001#4
Task: MIL-001#5
Task: MIL-001#6
Task: MIL-001#7
Task: MIL-001#8

.claude/skills/artifact/templates/MIL.md

@@ -0,0 +1,60 @@
+# @TITLE@
+
+## Metadata
+| Key | Value |
+| --- | --- |
+| ID | @ID@ |
+| CrossReference | @CROSSREF@ |
+| Language | @LANGUAGE@ |
+| Domain | @DOMAIN@ |
+
+## Version History
+| Date | Status | Author | Reviewer | Change | Commit |
+| --- | --- | --- | --- | --- | --- |
+| @DATE@ | Proposed | @AUTHOR@ | <reviewer S-ID> | Initial version | pending |
+
+---
+
+## Purpose
+
+<decision this gate supports>
+
+## Deliverable
+
+<concrete output evaluated at this gate>
+
+## Go / No-Go Criteria
+
+| # | Criterion (objectively checkable) | Go | No-Go |
+| --- | --- | --- | --- |
+
+## Dependencies
+
+| Depends on | Reason |
+| --- | --- |
+
+## Traceability
+
+| Business Case objective / KPI / user story | Reference |
+| --- | --- |
+
+## Ownership
+
+| Role | Stakeholder ID (SA) |
+| --- | --- |
+| Owner | |
+| Approving reviewer | |
+
+## Target Date
+
+YYYY-MM-DD — <consistency with Business Case constraints>
+
+## Tasks
+
+| # | Task | Summary | Needs its own Use Case/User Story? | Reference |
+| --- | --- | --- | --- | --- |
+| 1 | <task> | <what it involves and why - becomes the Issue body> | No | |
+
+---
+
+@LINKS@