hotfix(docs): exclude AirSim scene binaries from docs builds (0.20.8)

The same-dir plugin publishes the whole repo tree as site content, and the
downloaded Microsoft AirSim UE4 scenes (simulation/ms-airsim/assets/scenes/)
and environments (simulation/ms-airsim/environments/) were not in
exclude_docs, so every mkdocs build/serve on a machine with scenes fetched
copied ~15 GB of Unreal .debug binaries and zips into the site directory.
No pages or links reference either directory.

Bumps VERSION 0.20.7 -> 0.20.8 and records the change in the release notes.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Author: andrewjong

.env

@@ -12,7 +12,7 @@ PROJECT_NAME="airstack"
 # If you've run ./airstack.sh setup, then this will auto-generate from the git commit hash every time a change is made 
 # to a Dockerfile or docker-compose.yaml file. Otherwise this can also be set explicitly to make a release version.
 # auto-generated from git commit hash
-VERSION="0.20.7"
+VERSION="0.20.8"
 # Image-tag discriminator ONLY (appears in the image tag suffix, e.g. ..._robot-x86-64_dev).
 # No Dockerfile consumes it: "prebuilt" does NOT bake the built ros_ws into the image today —
 # a real prebuilt (workspace-baked) stage is future work. Keep "dev" (mounted code, built live).

docs/release_notes/index.md

@@ -21,6 +21,17 @@ its own notes. -->
 
 - Nothing yet.
 
+## 0.20.8 — 2026-09-04
+
+- **Docs builds no longer copy AirSim scene binaries.** The `same-dir`
+  plugin publishes the whole repo tree as site content, and the downloaded
+  Microsoft AirSim UE4 scenes (`simulation/ms-airsim/assets/scenes/`) and
+  environments (`simulation/ms-airsim/environments/`) were not excluded —
+  every `mkdocs build` or `docs serve` on a machine with scenes fetched
+  copied ~15 GB of Unreal `.debug` binaries and zips into the site
+  directory. Both directories are now listed in `exclude_docs`. No pages or
+  links referenced them.
+
 ## 0.20.7 — 2026-08-30
 
 - **Fixed 404s on every README-sourced docs page.** The `exclude_docs`

mkdocs.yml

@@ -20,6 +20,11 @@ exclude_docs: |
   **/ros_ws/install
   **/kit-app-template/**
   **/isaac_sim_data/**
+  # Downloaded AirSim UE4 scene binaries (fetched by assets/scenes/fetch_scene.sh)
+  # and environments: multi-GB, gitignored, never doc content. Without this the
+  # same-dir plugin copies them into every site build (~15 GB per build).
+  simulation/ms-airsim/assets/scenes/**
+  simulation/ms-airsim/environments/**
   # Fetched module checkouts (RFC #379 §9): the docs deploy workflows clone the
   # registry index + each registered module repo into the gitignored modules/
   # dir. Their content is linked from docs/modules/ (generated by