Upgrade Caddy v2.10.2 → v2.11.2, fix forge mirrors (#294)

## Summary
- Upgrade Caddy from v2.10.2 to v2.11.2 (7 CVE fixes across v2.11.1 and v2.11.2)
- Create `mirrors/caddy-l4` forge mirror for Layer 4 plugin
- Migrate all `~/code/3rd` clones on indri from `localhost:3001` to HTTPS `forge.ops.eblu.me/mirrors/` remotes
- Remove stale clones (`apple-silicon-detector`, `whisper.cpp`)
- Update caddy docs and service-versions tracking

## CVEs Fixed
- CVE-2026-27585 through CVE-2026-27590 (path/host bypass, TLS fail-open, FastCGI issues)
- Forward auth identity injection (privilege escalation)
- `vars_regexp` placeholder secret exposure
- Built on Go 1.26.1 (patches Go-level CVEs)

## What was done on indri (not in repo)
- `xcaddy build` with Gandi DNS + Layer 4 plugins → `~/code/3rd/caddy/bin/caddy` now v2.11.2
- Remotes updated: caddy, forgejo-runner, zot → `https://forge.ops.eblu.me/mirrors/*.git`
- Deleted: `~/code/3rd/apple-silicon-detector`, `~/code/3rd/whisper.cpp`

## Deployment and Testing
- [x] Ansible dry-run passed (`--tags caddy --check --diff`)
- [ ] Restart caddy LaunchAgent to pick up the new binary
- [ ] Verify all proxied services respond via `*.ops.eblu.me`
- [ ] Run `mise run services-check`

Reviewed-on: #294

docs/reference/services/caddy.md

@@ -1,6 +1,6 @@
 ---
 title: Caddy
-modified: 2026-02-12
+modified: 2026-03-15
 tags:
   - service
   - networking
@@ -87,14 +87,20 @@ Caddy has no authentication layer — it is a plain reverse proxy. Access contro
 
 ## Custom Build
 
-Caddy is built from source with the Gandi DNS plugin:
+Caddy is built from source using `xcaddy` with two plugins:
+
+- `github.com/caddy-dns/gandi` — ACME DNS-01 challenges via Gandi API
+- `github.com/mholt/caddy-l4` — Layer 4 (TCP/UDP) proxying
 
 ```bash
-# Build location
+# Source and build location (mirrored on forge)
 ~/code/3rd/caddy/bin/caddy
+
+# Build via mise task in the caddy clone
+cd ~/code/3rd/caddy && mise run build
 ```
 
-The build includes the `github.com/caddy-dns/gandi` plugin for ACME DNS-01 challenges.
+Forge mirrors: `mirrors/caddy`, `mirrors/caddy-gandi`, `mirrors/xcaddy`, `mirrors/caddy-l4`.
 
 ## Related