docs(P51): full presentation rework — scope, story arc, visuals, appendix

Major rework of both presentation decks based on leadership feedback.
Addresses: story arc, concept clarity, scope clarification, more visuals,
appendix for detail-heavy slides, and a complete Road to the North Star.

6 new mermaid diagrams:
- platform-works-03-scope-boundary (Upstream → Contract → ACDL → AWS)
- developer-experience-01b-scope-boundary (both consumer paths + scope)
- platform-works-04-confidence-signal (6 inputs → score → gate → decision)
- platform-works-05-attestation-flow (deploy → gate → approver → evidence)
- developer-experience-04-promotion-journey (dev → qa → prod → dr)
- road-to-north-star (v1.0 demo → v1.9 → v1.10 → v2.0 → North Star)

Both Marp decks restructured to 10 main + 6 appendix slides:

PW deck (17 slides):
1. Title
2. The Problem & The North Star (anti-goals moved to slide 3)
3. Where ACDL Sits in Your World (NEW — scope boundary, infra only)
4. The Contract-Driven Model (image: removed, infra inputs instead)
5. The End-to-End Flow
6. Zero-Trust by Default
7. Safety is Computed (NEW confidence signal diagram)
8. Security by Construction
9. Accountability & Audit (NEW attestation flow diagram, QA clarification,
   badge reclassification: dev=Testing, qa/prod/dr=Planned)
10. Testing vs. Planned (summary, full inventory in appendix)
11. The Vision Realized
+ Appendix: TOC, Platform-Managed Environments, Observability, Road to
  North Star, Full Inventory, Glossary

DX deck (16 slides):
1. Title
2. Where ACDL Sits in Your World (REPLACES Two Consumer Surfaces — scope
   boundary with both consumer paths)
3. The Contract — The Entire Consumer Surface (image: removed)
4. The Developer Feedback Loop
5. Versioned, Predictable Releases
6. Friendly Onboarding
7. Safe Promotion Path (NEW promotion journey diagram, rising bar
   annotated: dev=Testing, qa/prod/dr=Planned)
8. Safe Decommission
9. Self-Service Module Catalog
10. The Desired Outcomes
+ Appendix: TOC, Citizen Developer Experience, No Platform Code, Local
  Reproducibility, Road to North Star, Glossary

Story arc: every slide has an italic 'Story beat' line connecting it to
the narrative progression.

Scope clarification: ACDL is infrastructure only. Upstream is anything
(IDE, agentic SDLC, citizen dev vibe coding). ACDL provisions and governs
AWS resources; application deployment is upstream. Contract examples now
show infrastructure inputs (cpu, memory, desired_count, port) not image:.

QA attestation reclassification: 'Design tested' → 'Planned'. QA attests
to infrastructure readiness (contract + Terraform plan + evidence), not
application code. Dev is autonomous (Testing); qa/prod/dr are Planned.

Road to the North Star: phased timeline (v1.0 → v1.9 → v1.10 → v2.0 →
North Star), annotated 'proposed phasing, not formally planned.'

Also: scripts/sync_to_gl.sh added (GitLab mirror sync utility).

---ci---
phase: 51
milestone: v1.9
status: complete
requirements:
  covered: []
  partial: []
---/ci---

docs/presentations/README.md

@@ -115,9 +115,9 @@ Distill the source of truth (Step 1) into presenter-ready cues, indexed by
 the Marp deck (Step 2) slide structure:
 
 - **One section per Marp slide** — `## Slide N — Title`, matching the Marp
-  deck's 10-slide structure exactly. The Marp deck provides the indexing and
-  context (what the audience sees); the source markdown provides the content
-  (the speaker notes, the detail, the nuance).
+  deck's 10 main + 6 appendix slide structure exactly. The Marp deck
+  provides the indexing and context (what the audience sees); the source
+  markdown provides the content (the speaker notes, the detail, the nuance).
 - **3-6 talking point bullets per slide** — punchy, actionable cues distilled
   from the source markdown's speaker notes. NOT the speaker notes verbatim
   (those are too long and too contextual). These are prompts: "Land this
@@ -145,31 +145,57 @@ and re-distill.
 docs/presentations/
 ├── README.md                                  ← this file
 ├── how-the-platform-works.md                  ← Step 1: full source of truth
-├── how-the-platform-works-marp.md              ← Step 2: Marp deck (10 slides)
+├── how-the-platform-works-marp.md              ← Step 2: Marp deck (10 main + 6 appendix)
 ├── how-the-platform-works.html                  ← Step 3: rendered HTML (committed)
-├── how-the-platform-works-talking-points.md    ← Step 4: presenter cues (10 sections)
+├── how-the-platform-works-talking-points.md    ← Step 4: presenter cues (16 sections)
 ├── the-developer-experience.md                 ← Step 1: full source of truth
-├── the-developer-experience-marp.md            ← Step 2: Marp deck (10 slides)
+├── the-developer-experience-marp.md            ← Step 2: Marp deck (10 main + 6 appendix)
 ├── the-developer-experience.html               ← Step 3: rendered HTML (committed)
-├── the-developer-experience-talking-points.md  ← Step 4: presenter cues (10 sections)
+├── the-developer-experience-talking-points.md  ← Step 4: presenter cues (16 sections)
 └── assets/
     ├── puppeteer-config.json                   ← no-sandbox config for mmdc
     ├── mmd/                                     ← mermaid source files (Step 2 input)
     │   ├── platform-works-01-contract-driven.mmd
     │   ├── platform-works-02-end-to-end-flow.mmd
-    │   ├── developer-experience-01-two-surfaces.mmd
+    │   ├── platform-works-03-scope-boundary.mmd
+    │   ├── platform-works-04-confidence-signal.mmd
+    │   ├── platform-works-05-attestation-flow.mmd
+    │   ├── developer-experience-01b-scope-boundary.mmd
     │   ├── developer-experience-02-what-dev-does.mmd
-    │   └── developer-experience-03-no-cloning.mmd
+    │   ├── developer-experience-03-no-cloning.mmd
+    │   ├── developer-experience-04-promotion-journey.mmd
+    │   └── road-to-north-star.mmd
     └── png/                                     ← rendered PNGs (embedded in Marp)
         ├── platform-works-01-contract-driven.png
         ├── platform-works-02-end-to-end-flow.png
-        ├── developer-experience-01-two-surfaces.png
+        ├── platform-works-03-scope-boundary.png
+        ├── platform-works-04-confidence-signal.png
+        ├── platform-works-05-attestation-flow.png
+        ├── developer-experience-01b-scope-boundary.png
         ├── developer-experience-02-what-dev-does.png
-        └── developer-experience-03-no-cloning.png
+        ├── developer-experience-03-no-cloning.png
+        ├── developer-experience-04-promotion-journey.png
+        └── road-to-north-star.png
 ```
 
 ## Conventions
 
+### Appendix structure
+
+Each Marp deck has **10 main slides + 6 appendix slides** (16 total). The
+main 10 are the presentation; the appendix is for deep dives and Q&A backup.
+
+- **Main slides** (1-10): the story arc, high-impact, minimal text,
+  visual-heavy. These are what the audience sees during the talk.
+- **Appendix slides** (A1-A5 + TOC): detail-heavy slides moved out of the
+  main 10 to preserve the narrative flow. The appendix starts with a TOC
+  slide listing the contents, followed by detail slides and a glossary.
+- **The Road to the North Star** is a required appendix slide in both decks
+  — a phased timeline from v1.0 demo to the North Star, annotated as
+  "proposed phasing, not formally planned."
+- **The Glossary** is a required appendix slide in both decks — defines
+  acronyms (OIDC, ABAC, CMK, CMDB, RPO, HITL, VCS, NFR) for the audience.
+
 ### Maturity framing
 
 Every capability claim in a deck is tagged with one of three badges:
@@ -296,7 +322,7 @@ attachments to the Gitea release.
 
 ## Current decks
 
-| Deck | Source of truth (Step 1) | Marp deck (Step 2) | Rendered HTML (Step 3) | Talking points (Step 4) | Audience |
-|---|---|---|---|---|---|
-| How the Platform Works | `how-the-platform-works.md` | `how-the-platform-works-marp.md` | `how-the-platform-works.html` | `how-the-platform-works-talking-points.md` | CTO, Head of Cloud, Head of Infra, Head of DevOps |
-| The Developer Experience | `the-developer-experience.md` | `the-developer-experience-marp.md` | `the-developer-experience.html` | `the-developer-experience-talking-points.md` | CTO, Head of Cloud, Head of Infra, Head of DevOps |
+| Deck | Source of truth (Step 1) | Marp deck (Step 2) | Rendered HTML (Step 3) | Talking points (Step 4) | Slides | Audience |
+|---|---|---|---|---|---|---|
+| How the Platform Works | `how-the-platform-works.md` | `how-the-platform-works-marp.md` | `how-the-platform-works.html` | `how-the-platform-works-talking-points.md` | 10 main + 6 appendix | CTO, Head of Cloud, Head of Infra, Head of DevOps |
+| The Developer Experience | `the-developer-experience.md` | `the-developer-experience-marp.md` | `the-developer-experience.html` | `the-developer-experience-talking-points.md` | 10 main + 6 appendix | CTO, Head of Cloud, Head of Infra, Head of DevOps |