fix(docker): recreate storage directories and guard the chown (#705)

Backport of InvoiceShelf/InvoiceShelf#702 to 2.x. The chown half of it is
a 2.x-only fix — 3.x had already dropped that line.

storage/framework/{cache,sessions,views}, storage/logs and storage/app
hold no tracked content, only .gitignore stubs, so nothing guarantees they
exist inside a mounted volume. Docker seeds a named volume from the image
once, when it is empty, and never again — a volume created by an older
image keeps whatever it had through every upgrade. Without those
directories Laravel cannot boot and the sqlite branch cannot place its
database.

The unguarded `chown -R www-data:www-data storage` was worse than
ineffective. The image runs as www-data (uid 82), so chown of any file it
does not own returns EPERM, and under `set -e` that aborts the entrypoint.
A single uploaded file owned by the host user is enough to stop the
container from starting — on exactly the mounted-volume setups the chown
was meant to help. Verified against a built image: entrypoint exits 1
before this change, 0 after.

A mount the container genuinely cannot write to is not something the
entrypoint can repair, so it now says what is wrong and names the remedy
instead of failing later with `cp: can't create ...`.

docker/production/entrypoint.d/00-setup.sh

@@ -12,6 +12,32 @@ InvoiceShelf Version:  $version
 
 cd /var/www/html
 
+# These carry no tracked content — only .gitignore stubs — so a mount over
+# storage/ can arrive without them, and Laravel then dies at boot with "Please
+# provide a valid cache path" (the compiled view path is resolved with
+# realpath(), which returns false for a missing directory). Recreate them before
+# anything writes there, including the sqlite database placed in storage/app
+# below. See InvoiceShelf/docker#75, #69 and #77.
+echo "**** Ensuring storage directories exist ****"
+if ! mkdir -p \
+    storage/app/public \
+    storage/framework/cache/data \
+    storage/framework/sessions \
+    storage/framework/views \
+    storage/logs \
+    bootstrap/cache 2>/dev/null; then
+    echo "!!!! Cannot write to /var/www/html/storage."
+    echo "!!!! This container runs as uid $(id -u) (www-data), but the mounted"
+    echo "!!!! directory belongs to someone else — usually a bind mount pointing"
+    echo "!!!! at a host directory owned by your own user."
+    echo "!!!! Give that directory to uid 82 on the host and start again:"
+    echo "!!!!"
+    echo "!!!!     sudo chown -R 82:82 /path/to/your/storage"
+    echo "!!!!"
+    echo "!!!! See https://github.com/InvoiceShelf/docker/issues/77"
+    exit 1
+fi
+
 if [ ! -e /var/www/html/.env ]; then
     cp .env.example .env
     echo "**** Setup initial .env values ****" && \
@@ -35,8 +61,16 @@ fi
 
 echo "**** Setting up folder permissions ****"
 chmod +x artisan
-chown -R www-data:www-data storage bootstrap/cache
-chmod -R 775 storage bootstrap/cache
+
+# Only root may change ownership. The image runs as www-data, where chown of a
+# foreign-owned file is EPERM — and under `set -e` that stopped the container
+# from starting at all, on exactly the mounted-volume setups this was meant to
+# help. Skip it there rather than fail the boot; still applied when running as
+# root. See InvoiceShelf/docker#77 and #69.
+if [ "$(id -u)" = "0" ]; then
+    chown -R www-data:www-data storage bootstrap/cache
+    chmod -R 775 storage bootstrap/cache
+fi
 
 if [ ! -L /var/www/html/public/storage ]; then
     echo "**** Creating storage symlink (public/storage) ****"