…ney/build-upgrades

…ney/build-upgrades

Commit ec1b084 accidentally removed the connected components diagram
from the Connected Components section of the Pregel tutorial. The SVG
file exists at docs/src/img/pregel-diagrams/pregel-connected-components.svg
and should be shown like all other example sections in the tutorial.

The original commit was mislabeled as removing a 'Mermaid diagram' but
actually removed a rendered SVG <img> tag.

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

The connected-components SVG renders with only 2 nodes and 0 edges
(broken Mermaid render), making it useless in the tutorial. Reverting
the prior mistaken restore; the image reference should remain absent
from the Connected Components section.

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

…syntax

Chained undirected edges (A --- B --- C) fail to render in LR layout
with some Mermaid versions, producing a broken SVG with only 2 nodes.
Fix by using explicit two-node edge lines instead.

Also restore the connected-components diagram in the docs tutorial
(04-pregel-tutorial.md) which was previously removed due to the broken
SVG. With the correct rendering (18 nodes, 3 supersteps), the diagram
is now suitable for the tutorial.

Update generate_diagrams.py to use the fixed Mermaid syntax with a
comment explaining the workaround.

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

In Jupyter notebooks and docs, <figcaption> rendered as unstyled
block text indistinguishable from surrounding headings/paragraphs.

- Add a <style> block at the top of each notebook's first markdown
  cell to globally apply caption styling (smaller, italic, grey,
  centered) via the figcaption CSS selector
- Add equivalent inline style attributes to every <figcaption> in
  the Laika docs markdown files (04-pregel-tutorial.md and
  02-motif-tutorial.md) for the static site build

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

These SVG files were accidentally generated by running generate_diagrams.py
from the python/ working directory (causing relative output path to resolve
as python/docs/src/img/ instead of docs/src/img/).

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

Replace relative 'docs/src/img/...' path with one resolved from __file__
so the script writes to the correct location regardless of cwd.

Also includes minor SVG whitespace normalization from mmdc 0.4.1 re-render
(stroke-width:3px vs stroke-width: 3px — functionally identical).

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

The previous approach used per-element inline style= attributes on the 15
figcaptions across the two tutorial docs files. That only covered existing
files — any future doc page with a figcaption would be unstyled.

Replace with a proper Laika-level fix:
- Add docs/src/helium/custom.css with the figcaption rule
- Wire it into the Helium theme via .site.internalCSS() in LaikaCustoms.scala
  (required in Laika 1.0+; the old automatic CSS directory scanning is gone)
- Strip the now-redundant inline style= attributes from both tutorial docs

The <style> block in the notebooks (Jupyter rendering) is unchanged — it
remains the correct mechanism for notebooks since they do not go through Laika.

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

…s/97K edges

Every mention of the ~130K nodes / ~97K edges figures now names the specific
Stack Exchange dataset (stats.meta.stackexchange.com) so readers know exactly
which archive produces those numbers.

Updated in:
- docs/src/03-tutorials/04-pregel-tutorial.md
- docs/src/03-tutorials/02-motif-tutorial.md
- python/graphframes/tutorials/notebooks/Pregel.ipynb (cell 2)
- python/graphframes/tutorials/notebooks/Network_Motif_Finding.ipynb (cell 0)

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

<center> is a deprecated element that centers relative to its nearest
containing block. In Helium's layout that block spans the full page
(content column + both sidebars), so figures appeared shifted right.

Fix by:
- Adding figure { margin: 1em 0; text-align: center; } and
  figure img { max-width: 100%; height: auto; } to custom.css and
  the notebooks' <style> block — centering is now done via CSS
  within the content column's own containing block
- Removing all 30 <center>/<\/center> wrappers from the two tutorial
  docs and both notebooks; plain <figure> blocks are sufficient

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

Rename files to match requested order:
  1. GraphFrames Tutorials  (01-tutorials.md, unchanged)
  2. Stack Exchange Data Setup  (03-data-setup.md -> 02-data-setup.md)
  3. Motif Tutorial  (02-motif-tutorial.md -> 03-motif-tutorial.md)
  4. Pregel Tutorial  (04-pregel-tutorial.md, unchanged)

Update all cross-references in 9 files (docs + notebooks).

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

…play order

Renaming files for nav order breaks SEO (URL changes). Revert filenames
back to their originals and instead use Laika's navigationOrder in
directory.conf to control the display order independently of filenames:

  1. GraphFrames Tutorials  (01-tutorials.md)
  2. Stack Exchange Data Setup  (03-data-setup.md)
  3. Motif Tutorial  (02-motif-tutorial.md)
  4. Pregel Tutorial  (04-pregel-tutorial.md)

Also revert all cross-references in 9 files back to the original names.

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

The previous diagram showed 18 nodes across 3 supersteps in a flat LR
layout with no visual separation, making it hard to follow.

New strategy: three side-by-side panels (graph TB lays disconnected
subgraphs left-to-right) showing the minimum-label wave advancing
one hop per superstep across two separate components.

- Two components: {1,2,3} (3-node chain) and {4,5} (2-node pair)
- Node labels use vertex:componentLabel notation (e.g. 2:1 = vertex 2
  now carries component label 1)
- Left panel: Superstep 0 — each vertex starts with its own ID
- Middle panel: Superstep 1 — minimum label has advanced one hop
- Right panel: Converged — all vertices share the minimum ID of
  their component (1 or 4 respectively)
- Width bumped to 900px; caption updated to explain the notation

Co-authored-by: Russell Jurney <rjurney@users.noreply.github.com>

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Add a white background rect to rendered Mermaid SVGs so they display
correctly on dark-themed pages. Change figcaption color from grey to
white for readability.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>