docs(decision-lineage): add SLIDES.md — Marp deck for leadership demos (#103)

* docs(decision-lineage): add SLIDES.md — Marp deck for leadership demos

`examples/decision_lineage_demo/SLIDES.md` — a 21-slide Marp deck
that mirrors the 5-minute leadership pitch in DEMO_NARRATION.md and
the five EU-compliance questions in DEMO_QUESTIONS.md. Built with
Marp markdown so it ships as a single text file, version-controls
cleanly, and renders to PDF / PPTX / HTML via:

  marp SLIDES.md --pdf
  marp SLIDES.md --pptx
  marp SLIDES.md --html

Structure (21 slides):
  Title hero (EU AI Act framing + 7%-of-revenue penalty headline)
  Why this matters now — regulatory + product pressure side-by-side
  What we built — one-sentence pitch + pipeline diagram
  Section 1 — The data behind today's demo
    Six campaigns, six live agent runs (Nike Summer, Nike Winter,
      Adidas, Puma, Reebok, Lululemon)
    Three writers populate seven tables (BQ AA Plugin → SDK
      AI.GENERATE → SDK SQL DML)
    The graph the demo presents — 8 ads-domain node labels +
      9 ads-domain edge labels (CampaignRun, AgentStep,
      MediaEntity, PlanningDecision, DecisionOption,
      DecisionCategory, OptionOutcome, DropReason; CampaignActivity,
      NextStep, DecidedAt, ConsideredEntity, CampaignDecision,
      WeighedOption, HasOutcome, RejectedBecause, InCategory)
  Section 2 — Five regulator-shaped questions, answered live
    Q1 Right to explanation (Art. 86 / GDPR Art. 22)
    Q2 Bias / fairness audit (Art. 10, Art. 71)
    Q3 Human-oversight trigger (Art. 14) — empty-result hero
    Q4 Decision reproducibility (Art. 12, Art. 13)
    Q5 Systemic / pattern audit (Art. 17, Art. 60)
  Section 3 — What this unlocks
    Three takeaways (queryable posture, generalizable schema,
      composes with existing platform)
    Compliance-anchor map (Q1-Q5 × EU AI Act / GDPR / DSA)
    How fast can we ship this — phase timings, cost ("cents")
  Section 4 — Where to go next
    Open source pointers + bundle file map
    Anticipated VP-level Q&A primer
    Q&A hero closer

Theme: custom Marp theme on `gaia` base — Google Sans / Roboto
typography, #1a73e8 accent palette (matches Google Cloud brand),
gradient hero slides, code-block styling, two-column grids, stat
cards. Footer + pagination on body slides; off on lead slides.

README.md cross-references the new file from the docs-list and the
file map. Same 5-EU-question framing as DEMO_NARRATION.md and
DEMO_QUESTIONS.md so all three docs stay in lockstep.

* docs(decision-lineage): polish leadership slide deck

* docs(decision-lineage): check in SLIDES.html + SLIDES.pptx alongside source

Pre-rendered artifacts so reviewers can open the deck without
installing Marp.

  SLIDES.html  316K  — open in any browser
  SLIDES.pptx  5.6M  — editable in Google Slides / Keynote / PowerPoint

Both rendered from SLIDES.md with the Marp CLI:

  npx -y @marp-team/marp-cli@latest SLIDES.md --html
  npx -y @marp-team/marp-cli@latest SLIDES.md --html --pptx --no-stdin

The deck source (SLIDES.md) gains a "regenerate" note in the
opening HTML comment so future contributors know to refresh both
artifacts after edits. README.md file map lists the rendered
files.

The pptx is binary and won't show readable diffs in PRs — a
visible-diff regression caught in code review on SLIDES.md is the
defense; the rendered artifacts are convenience copies.

Author: caohy1988

examples/decision_lineage_demo/README.md

@@ -155,6 +155,10 @@ A talk track and a click-by-click walkthrough live alongside:
   `DecisionOption`, `OptionOutcome`, and `DropReason` included),
   step by step:
   [`DATA_LINEAGE.md`](DATA_LINEAGE.md)
+- Leadership-ready slide deck (Marp; renders to PDF / PPTX / HTML
+  via `marp SLIDES.md --html --pdf`) covering the same 5-question
+  narrative with the ads-domain vocabulary:
+  [`SLIDES.md`](SLIDES.md)
 
 ## File map
 
@@ -166,6 +170,9 @@ decision_lineage_demo/
 ├── BQ_STUDIO_WALKTHROUGH.md   # click-by-click in BQ Studio
 ├── DEMO_QUESTIONS.md          # 5 EU-compliance questions: BQ CA vs. direct GQL
 ├── DATA_LINEAGE.md            # canonical graph + richer demo graph lineage
+├── SLIDES.md                  # Marp deck source — leadership / Google-Next-style
+├── SLIDES.html                # rendered HTML (open in browser, no install needed)
+├── SLIDES.pptx                # rendered PowerPoint (editable in Google Slides / Keynote / PPT)
 ├── setup.sh                   # one-shot bootstrap
 ├── reset.sh                   # tear down dataset + rendered files
 ├── render_queries.sh          # sed-renders the .gql template