miscellaneous documentation improvements

.devcontainer/Dockerfile

@@ -11,7 +11,8 @@
 # We use a custom base image (that itself is based on Ubuntu). The
 # image contains additional helpers and programs that ease working
 # inside a Development Container. The image does *not* contain
-# programs or configuration files that are required to build unCORE!
+# programs or configuration files that you could not install manually
+# by yourself.
 FROM ghcr.io/georglauterbach/dev-container-base:1.0.0
 
 SHELL [ "/bin/bash", "-eE", "-u", "-o", "pipefail", "-c" ]
@@ -110,4 +111,7 @@ ENV RUSTUP_HOME="${DEV_CONTAINER_FILES_DIR}/rustup_home"
 # where we will work.
 WORKDIR "${WORKSPACE_DIR}"
 
+# We do not need not do we want to be `root`. The Development Containers
+# standard translates the UID of the host user so that no file conflicts
+# arise.
 USER ubuntu

.devcontainer/devcontainer.json

@@ -1,5 +1,9 @@
-// ref: https://code.visualstudio.com/docs/devcontainers/create-dev-container
-// ref: https://containers.dev/implementors/json_schema/
+// general::ref: https://code.visualstudio.com/docs/devcontainers/containers
+// creation::ref: https://code.visualstudio.com/docs/devcontainers/create-dev-container
+// json_schema::ref: https://containers.dev/implementors/json_schema/
+// variables::ref:
+//   https://github.com/microsoft/vscode-remote-release/issues/2697#issuecomment-609854675
+//   https://containers.dev/implementors/json_reference/#variables-in-devcontainerjson
 {
   "name": "unCORE",
   "build": {
@@ -15,6 +19,11 @@
       // workspace.
       "WORKSPACE_DIR_ARG": "${containerWorkspaceFolder}"
     },
+    "options": [
+      // Having plain output while building, and not the collapsed BuildKit output,
+      // makes finding problems easier.
+      "--progress=plain"
+    ]
   },
   "updateRemoteUserUID": true,
   "remoteUser": "ubuntu",
@@ -53,6 +62,11 @@
         "files.exclude": {
           "**/.git": true
         },
+        "files.watcherExclude": {
+          "**/.git/objects/": true,
+          "code/target": true,
+          "code/.dev_container/": true
+        },
         // ? extensions
         // * extensions::docsView
         "docsView.documentationView.updateMode": "sticky",