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/SD.md

@@ -0,0 +1,47 @@
+# @TITLE@
+
+## Metadata
+| Key | Value |
+| --- | --- |
+| ID | @ID@ |
+| CrossReference | @CROSSREF@ |
+
+## Version History
+| Date | Status | Author | Reviewer | Change | Commit |
+| --- | --- | --- | --- | --- | --- |
+| @DATE@ | Proposed | @AUTHOR@ | <reviewer S-ID> | Initial version | pending |
+
+---
+
+## Sequence: <operationName>
+
+**Realizes:** `operationName` in [OC-<n>]
+
+### Diagram
+
+```plantuml
+@startuml
+participant ":Controller" as C
+participant ":Collaborator" as X
+C -> X : message(args)
+activate X
+X --> C : result
+deactivate X
+@enduml
+```
+
+### Pattern Annotations
+
+| Pattern (GRASP / GoF) | Applied to | Rationale |
+| --- | --- | --- |
+
+### Postcondition Coverage
+
+| Postcondition (from contract) | Satisfied by message |
+| --- | --- |
+
+### Responsibility Check
+
+---
+
+@LINKS@