fix(restic): stop publishing rest-server passwords in systemd units

resticprofile schedule copies env-file values into the generated units, which
are 0644, so RESTIC_REPOSITORY (the rest-server basic-auth password included)
was readable by every local user on every restic host.

New playbooks/restic-repository-file.yaml:
- derives /etc/restic/repository (root 0400) from restic.env;
- uploads the profile switched to repository-file, but only when the live
  profile's sha matches the repo copy it was edited from (drift guard);
- checks the repository is reachable through the new profile (cat config);
- regenerates the units and verifies they exist and contain no rest:http.

Applied to ana-docker, fv-ml1 (configs/restic/ana-ml2), esh-docker-vm,
esh-vm-db, irv-ml1, nh3-dev and nh3-docker. An independent check across all
eight restic hosts (these seven plus esh-ml1) found 0 leaking units. nh3-docker's
scheduled unit ran a real backup afterwards (snapshot a29b889d). Each host's
URL and passphrase are vaulted as <host>/etc/restic/{repository,password}.

restic.env is kept (root 0600) because the per-host READMEs and the freshness
probe source it. A rotation must update the vault, restic.env and repository.

vm-esh-nas has no infra-ops account. Its in-place migration script is staged
for Prime to run with sudo, and its repo profile is pre-edited to match.

Also mirrors augaman-dev's 401df2d (compose header only). The config hash on
esh-ml1 is unchanged.

stacks/augaman/compose.yaml

@@ -1,6 +1,5 @@
-# augaman: the fleet's face-recognition service for Cicada (gitea pfi/augaman). The primary
-# instance is on esh-ml1 (CT 110 on esh-pve, RTX 2000E Ada 16 GB), with the gallery and the
-# backup. A second, fixtures-only instance runs on fv-ml1 (GPU_ID=1, no backup). Enroll,
+# augaman: the fleet's face-recognition service for Cicada (gitea pfi/augaman). It runs on
+# esh-ml1 (CT 110 on esh-pve, RTX 2000E Ada 16 GB), with the gallery and the backup. Enroll,
 # recognize, verify; buffalo_l (SCRFD + ArcFace w600k_r50) on ONNX Runtime CUDA. Canonical copy:
 # this file in pfi/augaman; the eshpfi stack mirrors it as stacks/augaman.
 #