mergedrop: bump to 1.0.1, rebuild from vid-merger source; fix stale source repo URL in build.sh

- config.json: tipi_version 1->2, version 1.0.0->1.0.1, updated_at bumped;
  added missing required fields supported_architectures (["amd64"]) and
  dynamic_config (true) so the app passes schema validation
- docker-compose.json: main service image mergedrop:1.0.0 -> mergedrop:1.0.1
- build/build.sh: default IMAGE_TAG 1.0.0 -> 1.0.1; default SOURCE_REPO
  corrected from stale video-merger.git to vid-merger.git
- build/README.md: corrected source repo pointer from video-merger to
  vid-merger

Image git.alexzaw.dev/alexz/mergedrop:1.0.1 is being built from
git.alexzaw.dev/alexz/vid-merger @ 9b27376 in a separate process.
Deploy chain (appstore update / app update) to be run separately once the
image build completes.

apps/mergedrop/docker-compose.json

@@ -4,7 +4,7 @@
   "services": [
     {
       "name": "mergedrop",
-      "image": "git.alexzaw.dev/alexz/mergedrop:1.0.0",
+      "image": "git.alexzaw.dev/alexz/mergedrop:1.0.1",
       "isMain": true,
       "internalPort": 8000,
       "environment": [