Rename phy-z-srv-gpu01 to phy-srv-gpu01; fix share analysis scripts

- rename host/group/folder everywhere to match the server's actual
  hostname and physical label
- share-analysis.ps1: sanitize the output filename prefix — '-Paths "D:"'
  produced 'D:-file-types.csv' and Export-Csv failed with 'path format
  not supported', so no CSVs were written
- share-analysis.ps1: new -FolderDepth so folders can be aggregated at
  D:\Abteilungen\<Share> level, which matches the share layout
- list-shares.ps1: -WithSize walks local paths instead of UNC when run on
  the server itself (UNC was orders of magnitude slower and looked stuck)
  and prints progress every 50k files

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

TODO.md

@@ -1,8 +1,8 @@
 # TODO
 
-## phy-z-srv-gpu01
+## phy-srv-gpu01
 
-Per [projektplan](server/phy-z-srv-gpu01/notes/20260710-projektplan.md) (§ references below).
+Per [projektplan](server/phy-srv-gpu01/notes/20260710-projektplan.md) (§ references below).
 Server is delivered; base setup + NVIDIA driver are done (see `SETUP.md`).
 
 ### Blocking the knowledge base (customer conversation)
@@ -32,8 +32,8 @@ Server is delivered; base setup + NVIDIA driver are done (see `SETUP.md`).
 - [ ] TLS: currently plain HTTP on `chat.phytron.local`; retrofit an internal CA
       certificate (AD passwords travel in clear text until then)
 - [ ] Hostname mismatch: server reports `phy-srv-gpu01`, repo/inventory/label use
-      `phy-z-srv-gpu01` — align
-- [ ] Finish base hardening in `SETUP.md` (ssh, updates) via `just run phy_z_srv_gpu01`
+      `phy-srv-gpu01` — align
+- [ ] Finish base hardening in `SETUP.md` (ssh, updates) via `just run phy_srv_gpu01`
 
 ### Done