Fix watch build to generate resources before the Pebble SDK packs them

.gitignore

@@ -7,6 +7,12 @@
 /watch/resources/img
 /watch/resources/app_icon.png
 
+# waf's own build lock file - regenerated every `pebble build`, holds
+# absolute machine paths and a full dump of the invoking shell's
+# environment variables. Was tracked accidentally; see the commit that
+# added this .gitignore line for the git rm --cached that untracked it.
+/watch/.lock-waf_linux_build
+
 # Durable backup of the same real birth data, outside dist/ so a dist/
 # wipe doesn't lose it — see the Makefile's `scripts` target. Never
 # commit this either.

watch/wscript

@@ -61,21 +61,24 @@ def configure(ctx):
 
 
 def build(ctx):
-    ctx.load('pebble_sdk')
-
     # Regenerate src/c/i18n_tables.auto.c from engine/i18n/*.lang,
     # resources/img/*.png from res/img/*.jpeg, and resources/app_icon.png
     # from res/app_icon_50x50_64_color.png, before compiling/bundling
     # anything - see each script's own doc comment. All three run eagerly
-    # (not as waf Tasks) since the bundle step below depends on their
+    # (not as waf Tasks) and must run *before* ctx.load('pebble_sdk')
-    # output existing; gen_card_images.py/gen_app_icon.py both skip
+    # below, since loading that tool in a build context immediately packs
-    # regenerating anything already up to date, so this stays cheap on
+    # resources/ into the app bundle - on a fresh checkout with no
-    # repeat builds. Requires Pillow (`pip install Pillow`) - see
+    # generated resources/img/ yet, that packing step would crash before
-    # watch/README.md.
+    # these scripts ever got a chance to create it. gen_card_images.py/
+    # gen_app_icon.py both skip regenerating anything already up to date,
+    # so this stays cheap on repeat builds. Requires Pillow (`pip install
+    # Pillow`) - see watch/README.md.
     subprocess.check_call([sys.executable, 'scripts/gen_i18n_tables.py'])
     subprocess.check_call([sys.executable, 'scripts/gen_card_images.py'])
     subprocess.check_call([sys.executable, 'scripts/gen_app_icon.py'])
 
+    ctx.load('pebble_sdk')
+
     engine_dir = ctx.path.parent.find_dir('engine/src')
     engine_nodes = [engine_dir.find_node(name) for name in ENGINE_SRCS]
     interp_dir = ctx.path.parent.find_dir('interpreter/src')