Add divisions.json — division presentation metadata (label, icon, color) (#592)

* Add divisions.json — presentation metadata (label, icon, color) per division

Establishes a source of truth for how each division (top-level agent directory)
is presented: a display label, a Lucide icon name, and a brand color. Lets the
Agency Agents app (and any other tooling) render divisions consistently —
including fixing "GIS" (was title-cased to "Gis") and covering `gis` +
`integrations`, which had no metadata before.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* Make divisions.json the source of truth + enforce in CI

divisions.json now drives the division set. Add scripts/check-divisions.sh
(CI: check-divisions.yml, runs on every PR with no path filter) which fails
if divisions.json disagrees with the directories on disk, the AGENT_DIRS
arrays in convert.sh / lint-agents.sh, or the lint-agents.yml path filters,
or if any entry lacks label/icon/color.

Fixes pre-existing drift surfaced by the new check: integrations was missing
from convert.sh and lint-agents.sh; integrations and strategy were missing
from lint-agents.sh and the lint workflow (so those agents weren't being
linted at all).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/lint-agents.sh

@@ -18,6 +18,7 @@ AGENT_DIRS=(
   finance
   game-development
   gis
+  integrations
   marketing
   paid-media
   product
@@ -26,6 +27,7 @@ AGENT_DIRS=(
   security
   spatial-computing
   specialized
+  strategy
   support
   testing
 )