Add devpi PyPI caching proxy role for indri

Set up devpi-server as a transparent PyPI caching proxy on indri,
accessible via Tailscale at pypi.tail8d86e.ts.net.

- Add ansible role with LaunchAgent (KeepAlive service via mise x)
- Add health checks to indri-services-check script
- Configure to listen on port 3141, data stored in ~/devpi

Note: Manual setup required on indri before provisioning:
1. Add devpi packages to ~/.config/mise/config.toml
2. Run mise install && mise x -- devpi-init --serverdir ~/devpi
3. Set up Tailscale service after ansible provisioning

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

ansible/roles/devpi/tasks/main.yml

@@ -1,13 +1,7 @@
 ---
-# Note: devpi is installed via mise (pipx/uvx), not managed here.
-# Add to ~/.config/mise/config.toml on indri:
-#
-#   [tools]
-#   "pipx:devpi-server" = { version = "latest", uvx = "true", uvx_args = "--with devpi-web" }
-#   "pipx:devpi-client" = { version = "latest", uvx = "true" }
-#
-# Then run: mise install
-# Initialize: mise x -- devpi-init --serverdir {{ devpi_serverdir }}
+# Note: devpi is installed via mise (pipx), not managed here.
+# Required packages: devpi-server, devpi-web, devpi-client
+# Initialization must be done manually: mise x -- devpi-init --serverdir {{ devpi_serverdir }}
 
 - name: Ensure devpi data directory exists
   ansible.builtin.file: