fix: retire leftovers of the removed $DSH_HOME/config.yaml personal overlay

The profile rework left references to the old entry modes behind. Renames
the user patch-layer API and its spec file (watchPersonalPatches ->
watchUserPatches, personal-config.spec.ts -> user-patches.spec.ts) and
retargets the prose that still named `config.yaml`, `--config`, raw-config
mode, and surface overlays: repository-plugin and mcp-memory READMEs, the
credentials-local anchor into app-boot, vendor manifest items 12-13, the
vendored include/hmr comments, and install.sh.

Restores the boot-failure guard the rework dropped with raw mode: the
built-bin case now boots `--profile web --patch <invalid>` and asserts the
settled diagnostic and exit 1, so the HMR initial-scan deadlock stays
covered; its orphaned raw fixture is renamed and the unused one deleted.
The superseded personal-config Agent Note and its superseding profile note
are now cross-linked.

apps/web/tests/pin-browse-picker.overlay.yml

@@ -1,4 +1,4 @@
-# Loader overlay for the W5 real-host smoke (`dsh web --config`): pin the
+# Loader overlay for the W5 real-host smoke (`dsh web --patch`): pin the
 # in-browser directory picker. The shipped row is `-auto`, which resolves to
 # the native OS chooser on a loopback bind with a local display — an
 # interaction a Playwright page cannot drive, so the resolved backend would